WO2024254268A2 - Systèmes de cathéter d'aspiration - Google Patents

Systèmes de cathéter d'aspiration Download PDF

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Publication number
WO2024254268A2
WO2024254268A2 PCT/US2024/032751 US2024032751W WO2024254268A2 WO 2024254268 A2 WO2024254268 A2 WO 2024254268A2 US 2024032751 W US2024032751 W US 2024032751W WO 2024254268 A2 WO2024254268 A2 WO 2024254268A2
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WIPO (PCT)
Prior art keywords
expandable
rings
distal tip
scaffold
supporting
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Ceased
Application number
PCT/US2024/032751
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English (en)
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WO2024254268A3 (fr
Inventor
Motasim Sirhan
John Yan
Benjamyn Serna
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Elixir Medical Corp
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Elixir Medical Corp
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Filing date
Publication date
Priority claimed from US18/482,711 external-priority patent/US12076504B2/en
Application filed by Elixir Medical Corp filed Critical Elixir Medical Corp
Publication of WO2024254268A2 publication Critical patent/WO2024254268A2/fr
Publication of WO2024254268A3 publication Critical patent/WO2024254268A3/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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Classifications

    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B17/00—Surgical instruments, devices or methods
    • A61B17/22—Implements for squeezing-off ulcers or the like on inner organs of the body; Implements for scraping-out cavities of body organs, e.g. bones; for invasive removal or destruction of calculus using mechanical vibrations; for removing obstructions in blood vessels, not otherwise provided for
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B17/00—Surgical instruments, devices or methods
    • A61B17/22—Implements for squeezing-off ulcers or the like on inner organs of the body; Implements for scraping-out cavities of body organs, e.g. bones; for invasive removal or destruction of calculus using mechanical vibrations; for removing obstructions in blood vessels, not otherwise provided for
    • A61B2017/22051—Implements for squeezing-off ulcers or the like on inner organs of the body; Implements for scraping-out cavities of body organs, e.g. bones; for invasive removal or destruction of calculus using mechanical vibrations; for removing obstructions in blood vessels, not otherwise provided for with an inflatable part, e.g. balloon, for positioning, blocking, or immobilisation
    • A61B2017/22065—Functions of balloons
    • A61B2017/22067—Blocking; Occlusion
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B17/00—Surgical instruments, devices or methods
    • A61B17/22—Implements for squeezing-off ulcers or the like on inner organs of the body; Implements for scraping-out cavities of body organs, e.g. bones; for invasive removal or destruction of calculus using mechanical vibrations; for removing obstructions in blood vessels, not otherwise provided for
    • A61B2017/22079—Implements for squeezing-off ulcers or the like on inner organs of the body; Implements for scraping-out cavities of body organs, e.g. bones; for invasive removal or destruction of calculus using mechanical vibrations; for removing obstructions in blood vessels, not otherwise provided for with suction of debris
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B2217/00—General characteristics of surgical instruments
    • A61B2217/002—Auxiliary appliance
    • A61B2217/005—Auxiliary appliance with suction drainage system
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
    • A61M25/00—Catheters; Hollow probes
    • A61M2025/0004—Catheters; Hollow probes having two or more concentrically arranged tubes for forming a concentric catheter system
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
    • A61M25/00—Catheters; Hollow probes
    • A61M25/0067—Catheters; Hollow probes characterised by the distal end, e.g. tips
    • A61M25/0074—Dynamic characteristics of the catheter tip, e.g. openable, closable, expandable or deformable

Definitions

  • E. Field of the Invention relates generally to medical devices and methods for their use. More particularly, the present invention relates to apparatus and methods for removing clot from a patient’s cerebral and other vasculature.
  • Every year millions of people worldwide suffer strokes caused by blood clots in the brain. Even when not fatal, these clots can lead to severe and permanent disability.
  • tissue plasminogen activator tPA
  • tPA tissue plasminogen activator
  • vascular thrombus tends to become more fibrous and/or firm up with time
  • the efficacy window for tPA is just a few hours after the clot first forms.
  • many patients’ clots are too mature to respond to tPA, such that perhaps two thirds of stroke victims were not being significantly helped by pharmaceutical treatment.
  • thrombectomy There are two primary approaches to mechanical thrombectomy, which may be used independently or in combination with each other depending on patient characteristics and physician preference.
  • the first is to use a catheter to apply a vacuum to the clot, in a technique known as direct aspiration.
  • the second is to use a stent retriever to snare and physically pull out the thrombus, optionally in combination with applying a vacuum to the clot through a separate aspiration catheter.
  • stent retrievers are small and flexible enough to access most clots, their ability to snag and remove a clot varies. In some cases, only a portion of the clot can be removed, and debris from the procedure can be released downstream causing secondary occlusions. Stent retrievers can also induce trauma to the vessel as they are dragged proximal pulling the clot with them. The struts of the retriever scrape the endothelium off the vessel walls, creating areas more prone to generating future occlusions.
  • Procedure time is also an issue with stent retrievers, since in addition to delivery and extraction time they typically require a significant time to settle into and secure the clot before the first removal attempt can be made. In an environment of blood-starved brain tissue, the difference in procedure times is very clinically significant on successful outcomes.
  • aspiration catheters The effectiveness of aspiration catheters depends on the ability of the catheter to vacuum the clot through the aspiration lumen of the catheter.
  • Current aspiration catheters are limited in diameter by the size of the accessory devices used by the physician to introduce the aspiration catheter into the anatomy, for example the hemostatic valve, introducer, and guiding membrane/catheter. Since most clots tend to be significantly larger than the aspiration catheter size, the small size of conventional aspiration catheters represents a challenge to successful aspiration, due to their inability to fully aspirate the clot on the first vacuum attempt and in the absence of breaking or fragmenting the clot.
  • Aspiration catheters having expandable distal tips that provide a larger distal opening for receiving the clot are described in commonly owned international application PCT/US2023/16449 (Attorney Docket No. 32016-730.601), entitled Aspiration Catheters with Supported Distal Regions, filed on March 27, 2023, the full disclosure of which is incorporated herein by reference.
  • PCT/US2023/16449 describes expandable tips which have been reinforced with expandable scaffolds with patterns which resist deformation and collapse even when exposed to high vacuum pressures during aspiration of a clot. While highly effective at removing clot after deployment, catheters having expandable aspiration tips are usually shown to be introduced using an “over-the-wire” protocol which in some instances can require additional guidewire introductions or exchanges.
  • a device that is capable of reaching clots in the brain in both the proximal and distal neuro anatomy, a device able to remove clots without fragmenting or without substantially fragmenting the clot, a device able to remove clots without causing secondary occlusions, a device able to remove clots reliably without requiring the use of a stent retriever or other supplementary device, a device able to reach the occlusion and retrieve the clots quickly, a device that does not scrape or otherwise induce trauma to the vessel wall at any point during the procedure, a device that is successful in retrieving the clot during the first aspiration attempt, and a device having an expandable distal tip that resists deformation and collapse even when exposed to high vacuum pressures during aspiration of a clot.
  • Aspiration catheters and catheter systems according to the present invention comprise a tubular catheter body having a proximal end, a distal end, and an aspiration lumen extending therebetween.
  • An expandable distal region with a central passage contiguous with the aspiration lumen of the tubular catheter body is disposed at the distal end of the catheter body and may be formed or separately integrally formed with the catheter body.
  • An expandable supporting structure is coupled, disposed, attached, or embedded within the expandable distal region, typically being embedded or laminated within an expandable membrane.
  • Aspiration catheters and catheter systems according to the present invention will find particular use in a patient’s cerebral vasculature but can also be used in the patient’s coronary and peripheral vascular.
  • the present invention provides an aspiration catheter comprising a tubular catheter body having a proximal end, a distal end, and a lumen extending therebetween, typically having a length in a range from 100 cm to 200 cm.
  • a distal tip structure comprises (a) an elongate rod having a proximal end and a distal end and (b) an expandable segment coupled, disposed, attached, or embedded to or within the distal end of the elongate rod of the catheter body.
  • the expandable segment has a central passage with a proximal opening and a distal opening and typically comprises or consists of an expandable membrane and a supporting scaffold configured to radially expand the expandable member.
  • the distal tip structure is configured to be advanced distally through the lumen of the tubular catheter body to overlap the expandable segment with the distal end of the tubular catheter body so that a seal is formed when the expandable segment is expanded in the distal end of the tubular catheter.
  • a distal tip structure separate from the tubular catheter body is advantageous in at least several respects.
  • the distal assemblies of the present invention can be combined with a variety of off-the-shelf guide catheters, guide sheaths, micro catheters, and other tubular components to form specialized aspiration catheters and systems for many purposes.
  • the separation of the catheter body and the distal tip structure allows alternative deployment protocols using rapid exchange guidewire delivery, over-the-wire guidewire delivery, and combinations thereof.
  • the present invention provides systems including the aspiration catheters of the present invention combined with a balloon catheter having an inflatable balloon at its distal end, where the inflatable balloon is configured to be inflated in the central passage of the expandable segment to expand and overlap the expandable segment with the distal end of the tubular catheter body to form the seal.
  • the expandable segments may be self-expanding, i.e., formed from elastic metals or other materials and delivered in a radially constrained confirmation.
  • the tubular catheter body comprises a guide catheter or a guiding sheath configured to be advanced over a guidewire.
  • the elongate rod has a solid core free from elongate passages.
  • the elongate rod has a hollow core or at least a portion of its length, e.g., the rod may be formed from hypo-tubing.
  • the expandable segment has a length in a range from 5 cm to 50, usually from 10 cm to 25 cm.
  • the scaffold comprises a plurality of radially expandable rings arranged along a longitudinal axis with circumferential spaces therebetween.
  • the scaffold may further comprise a multiplicity of supporting elements, where each supporting element has a base end and a free end, and the base end is attached to one of the radially expandable rings and the free end extends into an adjacent axial and/or circumferential space.
  • the scaffold may comprise a plurality of radially expandable rings arranged along a longitudinal axis with circumferential spaces therebetween.
  • the scaffold may further comprise a multiplicity of supporting elements, each supporting element having a base end and a free end, wherein the base end is attached to one of the radially expandable rings and the free end extends into an adjacent axial and/or circumferential space.
  • the present invention provides a distal tip structure for use in combination with a tubular catheter body having a proximal end, a distal end, and a lumen extending there between to form an aspiration catheter.
  • the distal tip structure typically comprises (a) an elongate rod having a proximal end and a distal end, and (b) an expandable segment coupled, disposed, or attached to or embedded within the distal end of the elongate rod of the catheter body and having a central passage with a proximal opening and a distal opening.
  • the expandable segment typically includes an expandable membrane and a supporting scaffold configured to radially expand the expandable member, and the distal tip structure is usually configured to be advanced distally through the lumen of the tubular catheter body to overlap the expandable segment with the distal end of the tubular catheter body so that a seal is formed when the expandable segment is expanded in the distal end of the tubular catheter.
  • the present invention provides a method for aspirating clot from a patient’s vasculature.
  • the method comprises positioning a distal tip of a tubular catheter body of an aspiration catheter or catheter system, as described above, in a patient’s vasculature near a region of clot.
  • the expandable segment of the distal tip structure is advanced through the lumen of the tubular catheter body to overlap with the distal end of the tubular catheter body, and a balloon is inflated within the central passage of the expandable segment to engage a vascular wall adjacent the region of clot and to form a seal with the distal end of the tubular catheter.
  • a negative pressure is applied to a proximal end of the lumen in the catheter body to aspirate the clot into the central passage of the expanded expandable segment.
  • the present invention provides an aspiration catheter comprising a tubular catheter body having a proximal end, a distal end, and a lumen extending therebetween.
  • An expandable segment is coupled, disposed, or attached to or embedded within at the distal end of the tubular catheter body and has a central passage contiguous with the lumen of the tubular catheter body.
  • the expandable segment includes an expandable membrane and a supporting scaffold configured to radially expand the expandable membrane, and the catheter body has a guidewire entry port located from 2 cm to 50 cm proximal of the distal end of the tubular catheter body, usually from 5 cm to 25 cm, and often from 10 cm to 25 cm.
  • the catheter body typically has a length from 100 cm to 200 cm
  • the guidewire entry port is formed through a wall of the catheter body and the guidewire exits through a distal port on the expandable segment.
  • the guidewire entry port is typically configured to inhibit fluid entry into the lumen of the catheter body when a negative pressure is applied to the lumen.
  • the guidewire entry port may be configured to at least partially collapse when a negative pressure is applied to the lumen.
  • the guidewire entry port comprises an elongate passage having a length and cross-sectional area which present a sufficient flow resistance to inhibit fluid entry into the lumen of the catheter body when a negative pressure is applied to the lumen.
  • these aspiration catheters comprise a guidewire tube having a proximal entry port and a distal exit port.
  • the guidewire tube may have a length from the proximal entry port to the distal exit port in a range from 10 cm to 50 cm.
  • the guidewire tube may be attached to an external surface of the catheter body.
  • the guidewire tube may extend at least partially over an external surface of the expandable segment.
  • the guidewire tube may be disposed on a wall of the catheter body lumen.
  • a guidewire or other secondary lumen or tube may extend the entire length of the catheter body, either including or excluding the length of the expandable tip.
  • Exemplary secondary lumens may be formed by extrusion of tubes having two contiguous lumens with a primary lumen typically being much larger that the guidewire or other secondary lumen.
  • Exemplary guidewire or other secondary tubes may be attached over an entire length of an external surface of the catheter body (optionally including the expandable distal tip), may be attached over an entire length of an internal lumenal surface of the catheter body (optionally including a central passage of the distal tip), or may be attached or otherwise formed over portions on the outer and internal lumenal surfaces.
  • the scaffold may comprise a plurality of radially expandable rings arranged along a longitudinal axis with circumferential spaces therebetween.
  • the scaffold may further comprise a multiplicity of supporting elements, each supporting element having a base end and a free end, wherein the base end is attached to one of the radially expandable rings and the free end extends into an adjacent axial and/or circumferential space.
  • the present invention provides an aspiration catheter, such as but not limited to a cerebral aspiration catheter, a coronary aspiration catheter, an arterial aspiration catheter, or a venous aspiration catheter, which comprises a tubular catheter body having a proximal end, a distal end, and an aspiration lumen extending therebetween.
  • the aspiration catheter has an expandable distal tip with a central passage (or a passage) contiguous with the aspiration lumen of the tubular catheter body.
  • An expandable supporting structure is attached to, embedded within, or otherwise coupled to the expandable distal tip of the tubular catheter body.
  • the expandable supporting structure may be attached to an outer or inner surface of an expandable membrane, but more often will be embedded or laminated within an expandable membrane, such as a polymeric membrane comprising one, two, three or more layers and being composed of one, two, three or more polymeric materials or other materials.
  • distal tip refers to a length or region at the distal end of the aspiration catheter.
  • the distal tip will typically be constructed differently than a proximal region or shaft of the aspiration catheter.
  • the distal tip will typically be configured to expand from a small diameter or from low-profile configuration or from as delivered configuration or from a delivery configuration to a large diameter or to a larger configuration or to an expanded configuration or to a deployed configuration, or to an enhanced extraction configuration, which has a larger clot aspiration force or clot extraction force when a vacuum is applied at a proximal end of the aspiration catheter and the distal tip is engaging a clot, wherein the expanded (or deployed) configuration of the distal tip remains substantially the same (or remains substantially expanded or deployed) when the vacuum is applied, thereby resisting collapse, typically being balloon expandable but sometimes being self-expanding.
  • the proximal region or shaft will typically have a fixed diameter along its length.
  • the fixed diameter of the proximal region or shaft may be constant or may vary along its length.
  • the distal tip in the as delivered configuration maybe a first clot extraction configuration while the expanded configuration maybe a second clot extraction configuration wherein the second clot extraction configuration has a larger extraction force than the first clot extraction configuration.
  • the expanded configuration maybe the clot extraction configuration or maybe the preferred clot extraction configuration as it typically has enhanced clot extraction force.
  • the distal tip typically terminates at the distal end of the aspiration catheter.
  • the supporting structure is typically in the form of a scaffold and is configured to permit radial expansion of the expandable membrane, typically by the application of a radially outward expansion placed within the supporting structure using a balloon or other expandable member, and is configured to enhance collapse resistance of the expandable membrane, particularly when the distal tip is engaging a clot (or blocked or plugged with clot) and a vacuum is being applied through the aspiration lumen, i.e., resist or prevent collapse of the expandable membrane or prevent a decrease in the lumen configuration of the expandable membrane, after expansion of the expandable supporting scaffold to the expanded configuration, or the supporting scaffold substantially maintain the expanded lumen configuration of the expandable membrane, when a vacuum is applied at a proximal end of the aspiration lumen while engaging a clot).
  • the supporting structure typically comprises a plurality of radially expandable rings arranged along a longitudinal axis with gaps therebetween (forming circumferential gaps between adjacent rings).
  • the radially expandable rings will typically comprise circular, square, rectangular, oval, helical, or other looped ring elements, where the looped ring elements are configured to non-elastically elongate (along their curved lengths) to permit circumferential expansion of the distal tip.
  • Exemplary ring elements can be formed as serpentine, zig-zag ring, box (square or rectangular), diamond, or other patterns comprising bends that non-elastically open in response to a radially outward force supplied by a balloon or other expandable deployment member or structure.
  • Exemplary rings maybe open cell design, closed cell design, combination of open and closed cell designs, or other.
  • Exemplary ring designs maybe formed from a tubular body, a bent wire, a patterned sheet rolled up into a tube, or printed, or other.
  • Exemplary open cell supporting structures may comprise serpentine and zig-zag ring patterns comprising struts joined by crowns, where the crowns comprise the “bends” which non-elastically open to allow radial and circumferential ring expansion. While every circular or circumferential ring may have an even or odd number of crowns and struts, each side or face of the ring may have even or odd number of crowns.
  • Each ring (including terminal ring(s)) preferably has at least 14,17, 12, 26, 30, 32, 34, 38, 40, 42, 60, 80, 100, 120, 140, 161, 160, 180, 200, or more crowns as counted on both side/face of the ring.
  • the total number of crown when counting both sides or faces of the ring is 14.
  • Higher crown numbers of 60, 80, 100, 120, 1400, 1600, 180, 200, and 400, and above are preferred when the supporting structure does not include additional supporting elements or when the supporting structure cells within a ring, or cells within a plurality of rings, or cells within each ring include a few supporting elements or include at least some but not all supporting elements, as described below.
  • crown numbers such as 14, 22, 26, 30, 32, 34, 38, 40, 42, 48, 60, and 80, are usually sufficient when the supporting structure includes at least some, or substantial number of supporting elements per ring, per at least some adjacent rigs, or per each ring of the expandable tip.
  • the number of crowns per ring, or per at least some adjacent rings, or per the rings along the length of the expandable supporting structure is configured to allow the expandable supporting structure to expand to the expanded configuration.
  • Enhanced circularity of the distal tip (expandable supporting structure and expandable membrane) in the expanded configuration can increase the aspiration lumen area, increase the vacuum force, resist lumen collapse and deformation when a vacuum is applied at a proximal end of the aspiration lumen and the distal tip is engaging a clot (or when the distal tip is blocked or plugged with clot or other substances). Furthermore, enhanced circularity resist deformation and/or kinking of the expandable distal tip in the as delivered configuration when the catheter is advanced into the vasculature. Maximizing circularity of a ring maybe further enhanced by having a small cell period and/or small cell amplitude.
  • the expandable supporting structure comprises a plurality of rings wherein at least some rings, preferably substantially all rings are configuration to have a large number of crowns, a small cell period, and a small cell amplitude., to have an enhanced circumferential circularity.
  • the ratio of (1) the number of bends, e.g. crowns, crowns per ring to (2) the circumference (perimeter) of the ring measured in millimeters (mm) is typically at least 3 crowns or bends per mm of circumferential length, frequently being at least 4 crowns or bends per mm of circumferential length, usually in a range from 3 to 18 crowns or bends per mm of circumferential length, typically from 4 to 15 crowns or bends per mm of circumferential length, and most preferably ranges from 4 to 12 crowns or bends per mm of circumferential length.
  • An increased number of crowns or bends or a high ratio of crown or bends per circumference length in each ring improves circularity of the distal tip (including the expandable supporting structure and the expandable membrane) in the expanded configuration, increases aspiration lumen area or maximizes lumen area, enhances vacuum force, and resist collapse of the distal tip when a vacuum is applied to the proximal end of the aspiration lumen and the distal tip is engaging a clot.
  • the higher number of crowns or crowns to circumference length ratio increases the resistance to collapse of the distal tip comprising the expandable membrane and expandable supporting structure when a vacuum is applied at a proximal end of the aspiration lumen and the distal tip is engaging a clot (or blocked with clot or other substances).
  • having a small cell period enhances circularity further.
  • having a small cell amplitude may further enhance circularity.
  • crowns per ring in the as delivered 2 mm outer diameter expandable tip will typically be sufficient to maintain circularity after expansion while 60, 80, 100, or more crowns per ring may be needed to provide equivalent support with supporting structures which do not include supporting elements.
  • the number crowns per ring in as delivered supporting structures having a 2mm outer diameter for example including supporting elements will typically range from 30 to 75, preferably from 40 to 75, and more preferably from 50 to 60.
  • the range for rings not having supporting structures will be from 60 to 150, preferably from 70 to 120, more preferably from 100 to 120.
  • the ratio of number of crowns to circumference in mm for embodiments including supporting elements will range from 3 to 10, preferably from 4 to 9, more preferably from 4.5 to 8, and most preferably from 5 to 7, while the ratio of crown number to circumference (measured in mm) for embodiments without supporting elements will range from 5 to 18, preferably from 6 to 12, more preferably from 8 to 12, and most preferably from 10 to 12.
  • Exemplary closed cell supporting structures may comprise “box” structures joined end-to-end by links in circular, helical, or other patterns.
  • the boxes will be joined by circumferential links to form circular rings which are in turned joined by axial links to form the supporting scaffold or other supporting structure.
  • the circumferential links may be arranged in a helical or spiral pattern to form a continuous series of rings, preferably without additional axial links or attachment points.
  • boxes will typically be square, diamond, or rectangular, boxes may have any closed polygonal structure which includes a plurality of straight (or sometimes curved) sides joined by bends. In some instances, circular and oval closed shapes could also be considered boxes within the scope of the present invention.
  • box structures will be configured to circumferentially elongate (expand) when a radial opening force is applied inside of the supporting structure in the distal tip of an aspiration catheter.
  • the expandable distal tip comprising the expandable supporting structure has an outer diameter in the as delivered configuration of about 1 mm, 2 mm, 3 mm, 4 mm, or of about 5 mm, or the expandable distal tip comprising the expandable supporting structure has an outer diameter in the as delivered configuration ranging from 1mm to 5mm.
  • the distal tip comprising the expandable supporting structure has an outer diameter in the as delivered configuration of about 7 mm, 8 mm, 9 mm, or of about 10 mm.
  • the distal tip has a cylindrical shape in the as delivered configuration.
  • the distal tip may have other shapes such as funnel, cone, an oblong, oval, or other shapes, in the as delivered configuration.
  • the distal tip comprising the expandable supporting structure wherein the distal tip has cylindrical shape, oblong shape, oval shape, cone shape, funnel shape, or other shapes, in the expanded configuration, wherein the distal tip outer diameter in the expanded configuration ranges from 2 mm to 1 0mm, preferably ranges from 3 mm to 8 mm, and more preferably ranges from 3 mm to 7 mm.
  • the outer diameter of the distal tip may vary along the length or about the circumference of the distal tip or may be fixed or constant along the length or about the circumference of the distal tip.
  • the scaffold or other supporting structure will also include supporting elements, which will help support spaces which open in in the support structure as the support structure is being expanded.
  • supporting elements which will help support spaces which open in in the support structure as the support structure is being expanded.
  • the struts will spread apart and leave unsupported spaces or gaps therebetween.
  • the gaps between adjacent rings will also be unsupported spaces, both before and after the supporting structure is radially expanded.
  • the membrane will lack support in those gaps, and the circularity and/or crush strength (crush resistance) of the expanded distal tip will both decrease.
  • such unsupported regions of the membrane will be at increased risk of invagination (collapse or partial collapse of the membrane and/or expandable supporting structure) when a negative pressure is applied to the aspiration lumen of the catheter when a clot is engaged, particularly when the open distal tip is partially or totally occluded with clot, or when the expandable tip is delivered to the vasculature in the as delivered configuration.
  • the supporting elements of the present invention will be configured to fill as many of the open space within a ring.
  • the spaces or gaps between axially adjacent rings will preferably be free from supporting elements (although axial links and other portions of the supporting structure will usually be present in some examples while in other examples the spaces or gaps between axially adjacent rings maybe free from any supporting elements or attachment points and free from any portions of the supporting structures).
  • the spaces between adjacent rings should have minimum number of supporting structure, if any, in order to enhance flexibility, particularly in the unexpanded delivery configuration.
  • the supporting elements of the present invention will cover or fill from 50% to 98% of the unsupported area within each ring, preferably from 65% to 95%, more preferably from 75% to 95%, and most preferably from 80% to 95%.
  • the supporting elements of the present invention in the expanded configuration (i.e., after deployment in a blood vessel), will cover or fill from 10% to 85% of the unsupported area within each ring, preferably from 15% to 85%, more preferably from 20% to 85%, and more preferably from 40% to 85%.
  • Preferred supporting elements will be “cantilevered” from the ring and be configured to fill or to support the openings or gaps within an “axial width” of a ring, usually remaining outside of the gaps and spaces between adjacent rings in order to support the distal tip after it has been radially expanded, without significantly reducing flexibility of the distal tip as it is being advanced into the vasculature, or without reducing flexibility of the distal tip as it is being advanced into the vasculature, or while maintaining the flexibility of the distal tip as it is being advanced into the vasculature.
  • Exemplary supporting element having a base (proximal) end and a free (distal) end.
  • the base end is usually attached to one of the radially expandable rings (e.g., to a ring structural element, such as a crown or a strut) and the free end is often oriented toward the gap between adjacent rings, usually not extending into the gap between adjacent rings in the as delivered configuration.
  • the expandable supporting structure comprises a plurality of supporting elements within each ring each having a width, a length, and thickness, sufficiently to support unsupported spaces (or region) within the ring, to prevent collapse or invagination (partial collapse) of the unsupported region, when a vacuum is applied to extract an engaged clot at the distal end of the aspiration catheter.
  • the expandable supporting structure comprises a plurality of circumferential rings wherein at least some rings comprise a plurality of supporting elements configured to resist collapse or resist invagination of the unsupported region when a vacuum is applied at a proximal end and a clot is engaging the distal end of the aspiration catheter.
  • the expandable supporting structure comprises a plurality of circumferential rings wherein at least some rings comprise at least some supporting elements configured to resist collapse or resist invagination of the unsupported region when a vacuum is applied at a proximal end and a clot is engaging the distal end of the aspiration catheter.
  • the supporting elements may extend into an adjacent gap between adjacent rings even prior to radial expansion of the distal tip, but preferably most or all of the supporting elements are configured to be recessed (or confined) within an axial width of the ring (or within an amplitude of a ring cell) prior to ring expansion and will extend further, protrude further, or emerge towards the adjacent gaps between adjacent rings or into the adjacent gaps between adjacent rings as the distal tip is radially expanded (or only after radial expansion of the distal tip, or during the radial expansion of the distal tip). It has been found that presence of the supporting structures in the gap between adjacent rings prior to distal tip expansion will reduce tip flexibility during advancement in the vasculature prior to distal tip deployment. Such loss of flexibility is undesirable.
  • the supporting elements deploy (or protrude, or extend further) towards a gap between two adjacent rings, or deploy into a gap between two adjacent rings, as the distal tip is expanded (or after the distal tip expansion) to enhance support of the expandable membrane after deployment of the distal tip without increasing stiffness of the distal tip during delivery (introduction and advancement) of the aspiration catheter into and through the patient’s vasculature.
  • the supporting elements may have various shapes and configurations such as I, T, U, M, Z, curved shaped, straight shaped, or other shapes and configuration to support or to enhance support of the unsupported segments of the expandable membrane, preferably without increasing stiffness of the distal tip.
  • the free end may have a flat shape, rounded shape, spherical shape, or other shapes.
  • the width of the supporting elements maybe the same along the length of the supporting elements or different.
  • the supporting elements may be tapered, either increasing or decreasing in width in a direction from the attached base end to the free distal end.
  • the dimensions of the supporting elements will preferably be selected to fill or occupy as much of the unfilled spaces or gaps within any given ring (but usually not between adjacent rings) in the supporting structure which may exist prior to expansion.
  • gaps between struts joined by crowns on a ring may be filled with supporting elements cantilevered from the inside curve of the crown, as illustrated in many embodiments herein.
  • the cantilevered supporting elements can be patterned fill virtually the entire space between the struts, leaving only cuts or very small separating lines therebetween.
  • the width of the supporting elements at the attached base end is approximately equal to or larger than the width of the structural element (e.g., strut, crown, or link) to the location at which the supporting element is attached.
  • the supporting elements and the expandable supporting structure are typically formed from the same material, in some instances they be formed from different materials or types of materials, e.g., (1) one may be formed from a metal and the other from a polymer or (2) one may be formed from a metal or a polymer and the other from a different metal or a different polymer.
  • the supporting elements are recessed in space between structural elements of the rings, e.g., in space between struts joined by crowns, so that the distal ends of the supporting elements do not extend substantially beyond peaks of adjacent crowns or other structural element into the gaps between adjacent rings in the as delivered configuration.
  • the supporting elements may have one base end and one free end, two free distal ends, three free distal ends, or more.
  • the supporting elements may have two or more base ends attached each to one or more structural element on one ring (the same ring). Such supporting elements may have one, two, three, or more distal free ends.
  • the supporting elements may be bisected to have at least two base ends, each base end being attached to a different structural element on a single ring.
  • the base ends of the supporting element may be attached to an axially inner or to an axially outer surface of a ring or of a ring’s structural elements comprising a crown, a strut, or a link.
  • the radially expandable rings are arranged within a cylindrical “envelope” prior to expansion.
  • the cylindrical envelope is a virtual space having an inner generally cylindrical surface and an outer generally cylindrical surface and an annular volume therebetween, where the radially expandable rings will be dimensioned and arranged to lie within this space prior to expansion.
  • the supporting elements are also configured to lie within this virtual cylindrical envelope prior to expansion of the rings.
  • the cylindrical envelope may have a diameter greater than, equal to, or smaller than that of the tubular catheter body prior to expansion.
  • the distal tip of the expandable supporting structure may be configured to expand into a cylinder, a cone, or a combination thereof after expansion to an expanded configuration.
  • the distal tip of the expandable supporting structure maybe configured to expand from a cylindrical configuration to an expanded cylindrical configuration, to an expanded cone shaped configuration, or to an expanded cone shaped distal tip configuration to maximize or to enhance the suction force when a vacuum is applied at a proximal end of the aspiration lumen.
  • the distal tip of the expandable supporting structure maybe configured to expand from a cylindrical configuration in the delivery configuration to a substantially cylindrical shaped configuration after the expandable supporting structure is expanded to an expandable configuration, wherein the expanded configuration is larger than the delivery configuration, or wherein the expanded configuration is larger than the as delivered configuration by a range from 1.1 to 4 times larger, preferable 1.3 to 3 times larger.
  • the distal tip of the expandable supporting structure is configured to expand from a cylindrical configuration to an expanded cone shaped configuration, at a proximal segment of the distal tip, and is continuously connected to an expanded cylindrical shaped configuration distal to the expanded cone shaped configuration.
  • the expanded configuration may be a combination of a long conical proximal base (there will usually be at least a short conical portion at the proximal end) attached to the proximal end of the shaft and a distal cylindrical portion.
  • a long conical proximal base there will usually be at least a short conical portion at the proximal end
  • a distal cylindrical portion A number of specific configurations are illustrated in the figures.
  • the expandable supporting structure is configured to expand in response to expansion of a balloon catheter within the expandable supporting structure.
  • the balloon catheter maybe configured to be delivered together with the aspiration catheter comprising the expandable supporting structure at the distal end, typically the balloon catheter being delivered together along with the aspiration catheter, within the aspiration lumen of the aspiration catheter, wherein after the distal end of the distal tip of the aspiration catheter is positioned adjacent to a clot, the balloon catheter is expanded to expand the expandable supporting structure to an expanded configuration, and is then deflated and withdrawn out of the aspiration catheter prior to applying a vacuum at a proximal end of the aspiration catheter to extract the clot.
  • the balloon catheter is delivered to the distal end of the aspiration catheter after the aspiration catheter is delivered to and positioned adjacent to a clot, wherein the balloon catheter is advanced through the aspiration catheter until the balloon reaches the expandable distal tip segment or reaches the expandable distal tip, then it is expanded to expand a distal tip segment of the aspiration catheter and is then deflated and removed from the aspiration catheter and a vacuum is applied at a proximal end of the aspiration catheter to remove (extract) the clot.
  • an expansion catheter having an expandable member at a distal end of the catheter, the expandable member is expanded, to expand an expandable distal tip comprising an expandable supporting structure (scaffold) and an expandable membrane, wherein the distal tip is incorporated into or coupled to the distal end of an aspiration catheter wherein the expandable member comprises a balloon, a scaffold, a cage, or other structure capable of expanding to expand the expandable supporting structure from an as delivered configuration to an expanded configuration.
  • the expandable member maybe polymeric, metallic, or other material wherein the member being expandable from an as delivered configuration, a crimped configuration, or a deflated configuration to an expanded configuration.
  • distal tip may be fully expanded along its entire length, often only a portion of the length of the distal tip may be expanded by the balloon or other expandable member depending on the patient anatomy or other circumstances.
  • the portion of the distal tip that is expanded can be controlled by adjusting the length of the balloon present in the distal tip during expansion and/or selecting an expansion balloon having a different length.
  • the expandable supporting structure of the distal tip of the aspiration catheter is formed from a deformable material, preferable plastically deformable material.
  • the expandable supporting structure is formed from a plastically deformable metal or metal alloy.
  • the expandable supporting structure is formed from a metallic material comprising stainless steel alloy, cobalt chrome alloy, platinum chromium alloy, or other metal or metal alloy.
  • the expanded shape of the supporting structure will usually be determined by the shape of the balloon or other expanding structure, i.e., expansion of a cylindrical balloon within the plastically deformable supporting structure will impart a cylindrical shape to the distal tip while expansion of a conical balloon will impart a conical shape to the distal tip.
  • the expandable supporting structure may be configured to self-expand when released from radial constraint.
  • the radial constraint may be positioned over the expandable supporting structure.
  • the radial constraint may be positioned within the expandable supporting structure (inner lumen) and is configured to release the expandable supporting structure in-vivo, to allow expansion of the expandable supporting structure.
  • the expandable supporting structure in one example is formed from a shape memory material such as nickel -titanium alloy, also known as NiTi or nitinol, or other shape memory material.
  • the supporting elements may have any one or more of a variety of shapes and attachment locations on the expandable structure.
  • the supporting elements may extend, in an axial direction to the radially expandable rings, towards the gap between adjacent rings, or extend into the gap between adjacent rings.
  • the supporting elements may extend in a circumferential direction to the radially expandable rings, typically attached to the outwardly curved surfaces of the crowns (peaks), extending circumferentially into an adjacent gap.
  • the supporting elements may extend in an axial direction to the radially expandable rings into the gap contained within or bounded by a ring’s axial width or is contained within or bounded by the space between structural elements of each ring or of the ring, typically attached to the curved surfaces of the crowns.
  • at least some of the supporting elements may comprise any one or more of linear and/or non-linear segments, may have expanded tips (forming contact pads as discussed hereinafter) at the free end.
  • the supporting elements may branch into two or more segments in a direction toward the free end. The supporting elements may have the same or different lengths or widths.
  • the supporting elements may have a length equal to or less than a length of an adjacent strut length in the as delivered configuration. In other examples, the supporting elements may have a length equal to or less than the ring cell amplitude in the as delivered configuration, or less than 1 time the ring cell amplitude in the as delivered configuration. In yet another example, the supporting elements may have a length equal to or less than the length of the ring period in the as delivered configuration. In other examples, the supporting elements may have a length greater than the ring cell amplitude only in the expanded configuration.
  • the supporting elements are attached to one or more of axial inner crown regions, axial outer crown regions, struts, mid strut, or attached to axial or circumferential links.
  • at least some of the radially expandable rings comprise a serpentine, zigzag, box, diamond, or other pattern including struts joined by crowns, and at least some of the adjacent rings are joined in one or more locations by axial links or attachment points using soldering, bonding, or fusing crown on adjacent rings for example, or as patterned.
  • At least some of the adjacent rings maybe joined end-to-end in a helical arrangement free from axial links or attachment points, and wherein preferably the amplitude on the at least some rings are fixed within each ring.
  • at least two adjacent rings, or at least some adjacent rings, of the expandable supporting structure distal tip have no more than two links or two attachment points joining the at least two adjacent rings (or joining the at least some adjacent rings).
  • the comprises a plurality of circumferentially expandable rings including struts joined by crowns, wherein one or more adjacent rings being axially separated by gaps and being unconnected, typically the one or more unconnected adjacent rings are located at the distal end of the distal tip of the aspiration catheter, and are held together by an expandable membrane attached to the one or more adjacent unconnected rings providing the distal tip enhanced flexibility in the as delivered configuration and allowing the one or more rings to expand from an as delivered configuration to an expanded configuration.
  • an expandable supporting structure comprising a plurality of adjacent expandable rings wherein along a length of the expandable structure, adjacent rings have two or less connections or attachment points joining the adjacent rings, preferably adjacent rings have one connection or attachment point joining the adjacent rings, wherein the length is the entire length of the expandable structure, or a segment along the axial length of the expandable structure, wherein the segment comprises two or more rings.
  • the expandable supporting structure comprising a plurality of adjacent rings joined end to end in a helical arrangement to enhance flexibility of the aspiration catheter to navigate tortuous anatomy in the as delivered configuration.
  • the adjacent rings in this example are not joined by links or attachment points on the adjacent rings, and the at least some adjacent rings each has fixed (or constant or same) ring cell amplitude, preferably all the at least some rings have the fixed (or constant or same) ring cell amplitude.
  • at least some rings maybe patterned into an open cell pattern, a closed cell pattern, or a combination of open and closed cell pattern along a length of the expandable scaffold.
  • the adjacent rings in the expandable supporting structure may be joined end-to-end in a helical arrangement.
  • Such helical arrangements will typically comprise a “smooth” helix free from additional curves or bends, i.e., a curve formed over on a conical or cylindrical surface that would become a straight line if the surface were unrolled into a plane.
  • one, two, three or more additional bends, curves or other secondary non-linearities can be superimposed over the helical rings to enhance bendability of the expandable structures, particularly in their crimped or reduced diameter configurations during delivery.
  • Such one, two, three or more additional bends, curves or other secondary non-linearities may be formed from an expandable supporting structure or a non-expandable structure.
  • the expandable supporting structure forms a helical coil.
  • the expandable membrane may comprise an elastic membrane, or an in-elastic membrane (stretchable membrane).
  • the elastic and/or in-elastic membrane may comprise one or more elastomers, polymeric material, or other material.
  • the expandable membrane is selected from a group consisting of NeuSoft UR862A, NeuSoft UR852A.
  • NeuSoft UR842A NeuSoft NEU 455-50A, NeuSoftTM 596- 50A, NeuSoft NEU 455-55A, NeuSoft NEU 455-60A NeuSoft NEU 455-65A, Tecothane AR-62A, T ecoflex EG 80A, Tecoflex EG 85 A, Tecoflex EG-93A, Tecoflex TT-1074A, Tecoflex TT-1085A Tecoflex TT-18095A, Elastollan S 50 A 15SPF Elastollan S 60 A 10W Elastollan S 60 A 10WH, Pellethane 2103 -70 A, Pellethane 70 A, Pellethane 2363 -80 A, Estane 2103-70A, ReZithane Rx50A, ReZilient 30 + 74% Tungsten, ReZilient 60A + 70% CSRM022 Tungsten, Rezithane Rx 50A, RTP 2700 S-30A, RTP 2700 S-40A , RTP 2700 S
  • the expandable membrane is comprised of a polymeric elastic membrane which may have isotropic properties, but in other instances may have anisotropic properties, for example the elastic membrane may have a higher elasticity in a circumferential or radial direction than in an axial direction.
  • the expandable membrane may be formed by heat shrinking over or onto the expandable supporting structure such as a scaffold.
  • the expandable membrane may be formed by laminating the expandable supporting structure such as a supporting scaffold between two or more layers of the polymeric material such as elastomer(s) material, elastomer(s) on an outer surface and an inelastic/stretchable polymeric material on an inner surface of the expandable structure, stretchable/inelastic material on both outer and inner surface of the expandable structure, or a stretchable material on the outer surface and an elastic material on the inner surface of the expandable structure.
  • the polymeric material such as elastomer(s) material, elastomer(s) on an outer surface and an inelastic/stretchable polymeric material on an inner surface of the expandable structure, stretchable/inelastic material on both outer and inner surface of the expandable structure, or a stretchable material on the outer surface and an elastic material on the inner surface of the expandable structure.
  • the two layers of elastomer(s), two layers one elastic and one stretchable, or two layers both stretchable may be bonded to each other over (sandwiching) the expandable supporting structure such as a supporting scaffold so that there is a seal between or bonding of the two layers as well as the two layers are sandwiching, bonding to, and/or adhering to the scaffold or other expandable structure.
  • the expandable membrane comprising a polymeric or other material configured to stretch and/or expand from an as delivered configuration to an expanded configuration, wherein the material is configured to expand from the as delivered configuration to a larger configuration ranging from 1.1 to 5 times larger than the as delivered configuration.
  • the expandable membrane is configured to have axial, radial, and/or circumferential stiffness to allow radial flexibility while maintaining axial push transmission.
  • the expandable membrane is configured to allow radial expansion of the expandable supporting structure and/or allow axial movement of the expandable supporting structure rings as the rings are being expanded from the as delivered configuration to an expanded configuration.
  • an aspiration catheter which comprises a tubular catheter body having a proximal end, a distal end, and an aspiration lumen extending therebetween.
  • the aspiration catheter has an expandable distal tip with a central passage contiguous with the aspiration lumen of the tubular catheter body, the expandable segment comprising an expandable supporting structure is attached to or embedded within an expandable membrane.
  • the expandable supporting structure is patterned from a tube, a bent wire, or rolled up patterned sheet. The tube, rolled up sheet, or bent wire in the preferred example are patterned into the expandable supporting structure being expandable from as delivered configuration to an expanded configuration.
  • an aspiration catheter which comprises a tubular catheter body having a proximal end, a distal end, and an aspiration lumen extending therebetween.
  • the aspiration catheter has an expandable distal tip with a central passage contiguous with the aspiration lumen of the tubular catheter body.
  • An expandable supporting structure is attached to or embedded within the expandable distal tip of the tubular catheter body, the tubular catheter body may be reinforced with a reinforcement structure over at least a portion of its length, proximal to the expandable tip, by one or more of a coil, a scaffold, a scaffold with supporting features, or other means.
  • the catheter body reinforcement structure comprising one or more of a coil, scaffold, or braid that may be formed continuously with the expandable supporting scaffold or other expandable supporting structure of the expandable tip.
  • the reinforcement structure and the expandable scaffold or other expandable supporting structure are formed from a patterned tube.
  • the reinforcement structure and the expandable scaffold or other expandable supporting structure are formed from a bent wire.
  • the reinforcement structure in the catheter body may be separately formed from the supporting scaffold of the expandable distal tip and are then coupled or joined together by one or more of solder, fusing, bonding, or weaving the structures together, overlapping them over a length segment at their interface.
  • an aspiration catheter which comprises a tubular catheter body having a proximal end, a distal end, and an aspiration lumen extending therebetween.
  • the aspiration catheter has an expandable distal end, with a central passage contiguous with the aspiration lumen of the tubular catheter body, the expandable distal end comprising an expandable supporting structure attached to or embedded within an expandable membrane.
  • the expandable distal end comprising the expandable supporting structure has a length ranging from 0.5mm to 50cm, preferably ranging from 1cm to 25cm, and more preferably ranging from 2cm to 10cm.
  • the expandable distal end may have a length spanning substantially the length of the aspiration catheter. In specific examples, the expandable distal end may have a length ranging from 50cm to 150cm. In a preferred example, the expandable distal end comprises an expandable distal tip wherein the distal tip comprises a segment of the expandable supporting structure attached to or embedded within an expandable membrane. In some specific examples, the expandable distal tip segment includes the expandable distal end segment. In some other instances, the expandable distal tip is the same as the expandable distal end.
  • At least some of the multiplicity of supporting elements may have their base ends each attached to a strut. In other preferred embodiments, at least some of the multiplicity of supporting elements may have their base ends each attached to either the inner curved surface or the outer curved surface of a crown.
  • the supporting elements may be extending or oriented axially, circumferentially, or at other angles or directions relative to the supporting scaffold or other expandable supporting structure, supporting scaffold rings, or structural elements of the scaffold rings.
  • the present invention provides an aspiration catheter having an alternative expandable supporting structure design.
  • the alternative aspiration catheter comprises a tubular catheter body having a proximal end, a distal end, and a lumen extending therebetween.
  • the expandable supporting structure is attached at or is incorporated into the distal end or to the distal tip of the tubular catheter body and has a central passage contiguous with the lumen of the tubular catheter body, and the expandable supporting structure includes an expandable membrane and an expandable scaffold or other expandable supporting structure configured to radially expand the expandable membrane.
  • the expandable membrane is typically elastically expandable, and the expandable scaffold or other expandable supporting structure is typically inelastically expandable, i.e., the scaffold plastically deforms to and maintains an expanded shape and size in response to radial expansion by a balloon or other radial expansion tool.
  • the expanded supporting structure “supports” the membrane in an expanded configuration.
  • the membrane could be plastically or otherwise inelastically expandable while the supporting structure is elastic or inelastic, but such embodiments are generally not preferred.
  • the expandable supporting structure may comprise a plurality of radially expandable rings arranged along a longitudinal axis, wherein at least some of the radially expandable rings comprise “expandable cells” having bends which can plastically deform to allow radial opening of the ring.
  • the cells may have an “open” configuration, such as U- shaped cells in serpentine rings and a V-shaped in zig-zag rings; squares, rectangular, or other regular or irregular polygons with one or more missing sides; and CD-shaped cells.
  • cells may have a “closed” configuration, such as diamond shaped, or boxshaped cells in boxed rings, wherein the box shape can be rectangular, square, or other or other regular or irregular polygonal shapes.
  • Supporting elements may be positioned inside or outside of an open cell.
  • the base of a cantilevered supporting element may be attached to the inside bent surface of a crown and positioned between adjacent struts in a U-shaped, V-shaped, or CDshaped open cell.
  • the base of a cantilevered supporting element may be attached to an outside bent surface of a crown and extend away from struts into a gap adjacent a U-shaped, V-shaped, or CD-shaped open cell.
  • Supporting elements may also be positioned inside or outside of a box or other closed cell.
  • the base of a cantilevered supporting element may be attached to an inside surface of the box and project into an interior space of the box.
  • the base of a cantilevered supporting element may be attached to an outside of the box or onto circumferential links which attaches the boxes or other closed cells together to form a ring.
  • at least one end of a supporting elements is attached to at least one location on a strut or crown or the ring of the radially expandable rings.
  • the supporting elements may be unattached to the supporting scaffold or other expandable supporting structure and are attached or coupled only to the expandable membrane so that they will reinforce the V-shaped, O-shaped, U-shaped, or square/box shaped spaces between struts to enhance resistance of the expandable membrane to collapse under vacuum/negative pressure when the distal tip is blocked or plugged with clot or other substances.
  • At least some of the supporting elements may extend in a circumferential direction from the radially expandable rings into the cell space (V-shaped, O-shaped, U-shaped, or square/box shaped space).
  • at least some supporting elements extend circumferentially from an outer crown region to an adjacent outer crown region, in one direction or in two opposite directions.
  • at least some supporting elements extend circumferentially from a strut to an adjacent strut, in one direction or in two opposite directions.
  • at least some of the supporting elements extend in an axial direction from the radially expandable rings into and/or beyond the cell space (V-shaped, O-shaped, U-shaped, or square/box-shaped space).
  • the supporting features are configured to shorten when the expandable supporting structure is expanded to an expanded configuration such that the supporting features length is equal to or less than the amplitude of the expandable ring cell, or the supporting features do not extend axially beyond the peak of an adjacent crown.
  • the supporting features are configured to deploy or project further when the expandable supporting structure is expanded to an expanded configuration providing enhanced support to the expandable membrane and providing the expandable membrane enhanced resistance to collapse when a vacuum is applied at a proximal end of the aspiration lumen.
  • the present invention provides an aspiration catheter having an expandable supporting structure design.
  • the aspiration catheter comprises a tubular catheter body having a proximal end, a distal end, and a lumen extending therebetween.
  • the expandable supporting structure is attached at or incorporated within the distal end (or distal tip) of the tubular catheter body and has a central passage contiguous with the lumen of the tubular catheter body, and the expandable supporting structure includes an expandable membrane and a supporting scaffold or other expandable supporting structure configured to radially expand the expandable membrane.
  • the expandable supporting scaffold or other expandable supporting structure comprises a plurality of radially expandable rings arranged along a longitudinal axis, wherein at least some of the radially expandable rings comprise a serpentine or zigzag or open other open pattern including struts joined by crowns forming a V-shaped, O-shaped, U-shaped, or open square/box shaped space therebetween.
  • a multiplicity of supporting elements are positioned in the V-shaped, O-shaped , U- shaped, or square shaped space to support the membrane in the V-shaped, O-shaped , U-shaped, or open square/box shaped space in the as delivered configuration and/or in the expanded configuration, and wherein the supporting scaffold or other expandable supporting structure resist collapse of the membrane in the space in the expanded membrane and scaffold or other expandable supporting structure configuration when a vacuum is applied at a proximal end of the aspiration lumen and the distal tip is blocked or plugged with clot or other substances, and wherein the supporting scaffold or other expandable supporting structure being capable to contract from the expanded configuration to a smaller configuration when the aspiration catheter is withdrawn into a guiding catheter having an inner lumen configuration smaller than the expanded configuration of the supporting scaffold or other expandable supporting structure.
  • the present invention provides an aspiration catheter having an expandable supporting structure design.
  • the aspiration catheter comprises a tubular catheter body having a proximal end, a distal end, and a lumen extending therebetween.
  • the expandable supporting structure is attached at the distal end (or distal tip) of the tubular catheter body and has a central passage contiguous with the lumen of the tubular catheter body, and the expandable supporting structure includes an expandable membrane and a supporting scaffold configured to radially expand the expandable membrane.
  • the expandable supporting scaffold comprises a plurality of radially expandable rings arranged along a longitudinal axis, wherein at least some of the radially expandable rings comprise a serpentine or zigzag or open pattern including struts joined by crowns forming a cell space there between.
  • a multiplicity of supporting elements are positioned in the cell space to support the membrane in the cell space in the as delivered configuration and/or in the expanded configuration, and wherein the supporting elements resist collapse of the membrane in the space in the expanded membrane configuration when a vacuum is applied at a proximal end of the aspiration lumen and the distal tip is blocked or plugged with clot or other substances, and wherein the supporting elements allow contraction the expanded supporting structure from an expanded configuration to a smaller configuration when the aspiration catheter is withdrawn into a guiding catheter having an inner lumen configuration smaller than the expanded configuration of the supporting structure.
  • the present invention provides a method for aspirating clot from a patient’s vasculature.
  • the method comprises positioning a distal end of the expandable supporting structure of any of the aspiration catheters, as described, in the patient’s vasculature at or near a region of clot.
  • the expandable supporting structure is expanded, typically by balloon expansion (but alternatively by self-expansion), to engage a clot or to engage a vascular wall adjacent the region of clot.
  • a negative pressure vacuum
  • the present invention provides a method for aspirating clot from a patient’s vasculature.
  • the method comprises positioning a distal tip of the expandable supporting structure of any of the aspiration catheters, as described, in the patient’s vasculature at or near a clot.
  • the expandable supporting structure is expanded to an expanded configuration, typically by balloon expansion but alternatively by self-expansion, to engage a clot or to engage a vascular wall adjacent to a clot.
  • a vacuum is applied to a proximal end of the lumen in the catheter body to aspirate the clot into the central passage of the expanded expandable structure, at least a portion of the expandable supporting structure is optionally contracted from the expanded configuration to a smaller configuration, prior to removal from the vasculature.
  • the present invention provides an aspiration catheter comprising a tubular catheter body having a proximal end, a distal end, and a lumen extending along a longitudinal axis.
  • a distal tip has a proximal end incorporated into or is attached to the distal end of the tubular catheter body and a central passage (aspiration lumen) longitudinally contiguous with the lumen of the tubular catheter body.
  • the distal tip is adapted to expand from an as delivered configuration to a radially expanded configuration or from a radially contracted configuration to a radially expanded configuration in response to a radially outward expansion force applied within the distal tip segment, and the distal tip comprises an expandable membrane and an expandable supporting structure such as a scaffold where the expandable scaffold or other expandable supporting structure comprises a plurality of rings spaced-apart along the longitudinal axis with gaps therebetween. At least some of the rings comprise a malleable metal or metal alloy configured to plastically deform to circumferentially expand the scaffold or other expandable supporting structure in response to the radially outward expansion force applied from within the distal tip.
  • the expandable membrane is attached to an inner and/or outer surface of the expandable scaffold or other expandable supporting structure.
  • the expandable scaffold or other expandable supporting structure is embedded in or within the expandable membrane, wherein the expandable membrane comprises at least two membrane one is attached to an outer surface of the expandable scaffold or other expandable supporting structure while the other is attached to an inner surface of the expandable scaffold or other expandable supporting structure.
  • an aspiration catheter comprising an expandable tip, wherein the expandable tip comprises an expandable membrane and an expandable supporting structure such as a scaffold where the expandable scaffold or other expandable supporting structure comprises a plurality of rings spaced-apart along the longitudinal axis with gaps there between and within each of the rings, wherein the rings comprise structural elements comprising struts and crowns.
  • the expandable scaffold or other expandable supporting structure is embedded in or within the expandable membrane, wherein the expandable membrane comprises at least one membrane wherein the at least one membrane is softened and/or melted over an outer surface of the expandable scaffold or other expandable supporting structure and/or over an inner surface of the expandable scaffold or other expandable supporting structure, allowing the expandable membrane to protrude or flow into the gaps present within the ring structural elements and gaps present between adjacent rings, adhering to the rings and rings structural elements, providing a unified (an integrally) expandable scaffold/membrane(s) system, expandable from contracted or as delivered configuration to an expanded larger configuration.
  • the expandable membrane in a preferred aspect, covers an outer and/or an inner surface of the expandable structure, and also covers wherein covers comprises one or more of fills, flows into, or protrude into at least some gaps present within each ring of the expandable scaffold or other expandable supporting structure and gaps present between adjacent rings of the expandable scaffold or other expandable supporting structure, wherein the flowing membrane adheres sufficiently to the scaffold or other expandable supporting structure rings structural elements to provide a unified system (integrated system) being capable to expand from an as delivered configuration to an expanded configuration as an integrated system.
  • unified system integrated system
  • the expandable membrane in a preferred aspect flows into gaps present between each of the rings, within each of the rings structural elements comprising struts joined by crowns, wherein the one or more expandable membranes in a preferred aspect covers an outer surface and/or inner surface of the expandable scaffold or other expandable supporting structure, covers at least some side surfaces of the expandable scaffold structural elements, preferably covers substantially all side surfaces of the expandable scaffold structural elements, and covers substantially all gaps between adjacent rings of the expandable scaffold or other expandable supporting structure.
  • the expandable scaffold or other expandable supporting structure in a preferred aspect comprises an outer surface, an inner surface, and two side surfaces.
  • an expandable scaffold or other expandable supporting structure is formed from a bent wire comprising an outer surface and an inner surface.
  • the scaffold or other expandable supporting structure has an as delivered configuration or a radially contracted (e.g., crimped) delivery configuration and an expanded deployed configuration.
  • the radially contracted configuration has a maximum outer diameter in a range from 0.5 mm to 30 mm, usually from 1.0 mm to 5 mm, and more usually from 2mm to 5mm
  • the radially expanded configuration has a maximum outer diameter in a range from 1 mm to 60 mm, preferably from 1.5 mm to 45 mm, more preferably from 3 mm to 45 mm.
  • the distal tip may be configured to expand from an initial cylindrical shape to an enlarged cylindrical configuration in response to the radially outward expansion force applied within at least a portion of the distal tip.
  • the distal tip is configured to expand from an initial cylindrical shape to an enlarged conical configuration in response to the radially outward expansion force applied within at least a portion of the distal tip.
  • the enlarged conical configuration ends at the distal end of the distal tip, providing the largest area (cross sectional area) for clot extraction.
  • the tubular catheter body may have a working length from the proximal end to the distal end in a range from 50 cm to 200 cm, an outer diameter in a range from 0.5 mm to 30 mm, and an inner lumen diameter from 0.25 mm to 25 mm.
  • the distal tip may have a bending resistance below 1 N, preferably below 0.5 N, more preferably below 0.3 N, and most preferably below 0.2 N in its initial radially contracted configuration or in the as delivered configuration as measured by a three-point flexure test (described in more detail below).
  • the distal tip may also have a collapse pressure (vacuum) at or above 0.5 atm, preferably at or above 0.75 atm, and more preferably at about 1 atm, in its radially expanded configuration, and most preferably above 1 atm in its radially expanded configuration when a vacuum is attached to a proximal end and a clot (or plug) is engages and blocks the open distal end of the distal tip.
  • the distal tip may have a bending resistance range from 0.1N to 2N, preferably range from 0.1N to 0.5N, more preferably range from 0.1N to 0.35N, and most preferably range from 0. IN to 0.2N, in its initial radially contracted configuration or in the as delivered configuration.
  • the bending resistance is a measure of the distal tip flexibility to navigate tortuous anatomy. A lower the bending resistance indicates a higher flexibility and a better ability of the distal tip to navigate tortuous anatomy.
  • the bending resistance of the distal tip may be measured by a three-point flexure test, such as ASTM F2606 Standard Guide for Three-Point Bending of Balloon Expandable Vascular Stents and Stent Systems or equivalent.
  • a section of the catheter rests perpendicularly on two lower static supports with a wedge centered between them. The spacing of the two supports is 13 mm.
  • the middle of the supported catheter section is displaced by lowering the wedge which is held in an upper grip of an Instron Tensile Tester (Instron, Norwood, MA, USA) at a deflection rate 5.0 mm/min while measuring the resistance force.
  • the test is ended when the displacement reaches 2 mm (approximately 15% of Span Length).
  • the three-point bending resistance for that catheter section is equal to the maximum deflection force measure during the test.
  • the collapse pressure is the vacuum or negative pressure which, when applied at the proximal end of the catheter body lumen, will cause the distal tip to at least partially collapse when distal tip is fully occluded.
  • at least partially collapse it is meant that an irreversible contraction (contraction that is not resolved after applied vacuum is stopped) of more than 5%, of more than 10% or of more than 15% of the distal tip inner lumen diameter or configuration.
  • the distal tip inner lumen diameter or configuration comprising a plurality of expandable rings under applied vacuum in the expanded (deployed) configuration is configured to have the expandable rings in the expanded configuration resist collapse when a vacuum is applied at a proximal end of the aspiration catheter and the distal tip is blocked or plugged with clot or other substances; or is configured to resist collapse by contracting no more than 5%, no more than 10%, or no more than 15% of any of the distal tip rings configurations when the rings are under applied vacuum in the expanded configuration of the rings and the tip engaging a clot (or a plug), or preferably by contracting no more than 10%, of the expanded configuration under vacuum, or most preferably by contracting no more than 5% of the expanded configuration under vacuum.
  • the distal tip inner lumen diameter or configuration comprising a plurality of expandable rings under vacuum of about latm, in the expanded deployed configuration, resist collapse by radially contracting by no more than 5% of any of the expandable rings, wherein the radial contraction of no more than 5% is substantially reversible to the expanded configuration when the vacuum or negative pressure applied at a proximal end of the catheter body lumen with the central passage of distal tip is removed or stopped (i.e., the distal tip inner lumen diameter or configuration expands to the larger expanded configuration.
  • the present invention provides an aspiration catheter comprising a tubular catheter body having a proximal end, a distal end, and a lumen extending along a longitudinal axis.
  • a distal tip has a proximal end attached to the distal end of the tubular catheter body and a central passage longitudinally contiguous with the lumen of the tubular catheter body (aspiration lumen).
  • the distal tip is adapted to expand from an as delivered configuration to a radially expanded configuration or from a radially contracted configuration to a radially expanded configuration in response to a radially outward expansion force applied within the distal tip, and the distal tip comprises an expandable membrane and an expandable supporting structure such as a scaffold where the expandable scaffold or other expandable supporting structure comprises a plurality of rings spaced-apart along the longitudinal axis with gaps therebetween. At least some of the rings comprise a malleable metal or metal alloy configured to plastically deform to circumferentially expand the scaffold or other expandable supporting structure in response to the radially outward expansion force applied from within the distal tip.
  • the expandable tip comprising an expandable membrane and expandable scaffold or other expandable supporting structure are configured to radially contract by no more than 15%, preferably by no more than 10%, and more preferably by no more than 5% of any of the expandable rings, when a vacuum is applied to a proximal end of the aspiration lumen and the distal tip is engaging a clot (or plug), and to passively expand (without outward expansion force applied within the distal tip by an expandable member), wherein the expanded configuration is larger than the contracted configuration when the applied vacuum is stopped (or removed), preferable wherein the expanded configuration is larger than the contracted configuration and is substantially the same as the expanded configuration prior to applying any vacuum.
  • the distal tip inner lumen diameter or configuration under vacuum of about latm in the expanded deployed configuration, radially contracts by no more than 15%, preferably by no more than 10%, and more preferably by no more than 5% resisting collapse, wherein the radial contraction is substantially reversible when the vacuum or negative pressure applied at a proximal end of the catheter body lumen with the central passage of distal tip is removed or stopped (i.e., the distal tip inner lumen diameter or configuration expands to a larger configuration, larger than the contracted configuration under vacuum).
  • the present invention provides an aspiration catheter comprising a tubular catheter body having a proximal end, a distal end, and an aspiration lumen extending along a longitudinal axis.
  • a distal tip has a proximal end attached to the distal end of the tubular catheter body and a central passage longitudinally contiguous with the aspiration lumen of the tubular catheter body.
  • the distal tip is adapted to expand from an as delivered configuration (or from a first extraction configuration) to a first radially expanded configuration in response to a radially outward expansion force applied within the distal tip, wherein the first radially expanded configuration (second extraction configuration or extraction configuration) ranges from 1.1 to 2 times the as delivered configuration, and wherein the distal tip comprises one or more expandable membranes and an expandable scaffold where the expandable scaffold comprises a plurality of expandable rings spacedapart along the longitudinal axis with gaps therebetween, and wherein the expandable rings comprise structural elements including struts joined by crowns.
  • At least some of the rings comprise a malleable metal or metal alloy configured to plastically deform to circumferentially expand the scaffold or other expandable supporting structure in response to the radially outward expansion force applied from within the distal tip.
  • the expandable tip comprising the one or more expandable membranes and expandable scaffold comprising a plurality of expandable rings are configured to radially contract to a first contracted configuration wherein the first contracted configuration is smaller than the first expanded configuration but larger than the as delivered configuration, preferably wherein the first contracted configuration is smaller than the first expanded configuration by no more than 15%, preferably by no more than 10%, and more preferably by no more than 5% smaller than the first expanded configuration when a vacuum is applied to a proximal end of the aspiration lumen wherein the applied vacuum, or when the applied vacuum ranges from 0.75 atm to 1 about atm, and wherein the expandable tip is configured to passively expand, to a second expanded configuration wherein the second expanded configuration is larger than the first contracted configuration and equal to or smaller than the first expanded configuration, when
  • the expandable distal tip has a length ranging from 0.5 mm to 500 mm, preferably having a length ranging from 1 cm to 50 cm, and more preferably ranging from 1 cm to 25 cm.
  • the one or more expandable membranes of the expandable distal tip in one example extends proximally beyond the proximal end of the distal tip of the aspiration catheter.
  • the one or more expandable membranes of the expandable distal tip has about the same length as the expandable scaffold and are both incorporated within or attached at their proximal end to the distal end of the aspiration catheter.
  • the one or more expandable membranes extend from the distal end of the distal tip to a proximal end of the aspiration catheter.
  • the distal tip comprising an expandable scaffold or other expandable supporting structure has a minimum bending radius without deformation and/or kinking of 5 mm, preferably 3 mm, and more preferably 2 mm in its as delivered configuration or the radially contracted configuration, and preferably, a minimum bending radius without deformation and/or kinking of 10 mm, preferably 6 mm, and more preferably 2mm in its radially expanded configuration.
  • Minimum bending radius may be determined by bending the distal tip about a cylinder of a known radius and observing if the distal tip deforms and/or kinks.
  • the rings of the expandable scaffold or other expandable supporting structure span a length in a range from 0.25 mm to 500 mm or more measured in a longitudinal direction, preferably a range from 1 mm to 100 mm, more preferably a range from 10 mm to 70 mm, and most preferably range from 20 mm to 50 mm.
  • the present invention provides an aspiration catheter comprising a tubular catheter body having a proximal end, a distal end, and an aspiration lumen extending along a longitudinal axis.
  • a distal tip has a proximal end incorporated into the distal end of the tubular catheter body and a central passage longitudinally contiguous with the aspiration lumen of the tubular catheter body.
  • the distal tip is adapted to expand from an as delivered configuration to a first radially expanded configuration in response to a radially outward expansion force applied to the distal tip, wherein the first radially expanded configuration ranges from 1.1 to 2 times the as delivered configuration, and wherein the distal tip comprises one or more expandable membranes and an expandable scaffold where the expandable scaffold comprises one or more expandable rings spaced-apart along the longitudinal axis with gaps therebetween, and wherein the expandable rings comprise structural elements including struts joined by crowns.
  • the one or more rings are composed of a malleable metal or metal alloy (or alternatively are formed from shape memory metallic alloy) configured to plastically deform to circumferentially expand the scaffold or other expandable supporting structure in response to the radially outward expansion force applied from inside the distal end or distal tip.
  • the expandable scaffold consists of one, two, or three expandable rings.
  • the expandable scaffold consists of one expandable ring.
  • the distal tip comprising an expandable scaffold or other expandable supporting structure has a minimum bending radius without deformation and/or kinking of 5 mm, preferably 3 mm, and more preferably 2 mm in its as delivered configuration or the radially contracted configuration, and preferably, a minimum bending radius without deformation and/or kinking of 10 mm, preferably 6 mm, and more preferably 2mm in its radially expanded configuration.
  • Minimum bending radius may be determined by bending the distal tip about a cylinder of a known radius and observing if the distal tip deforms and/or kinks.
  • the rings of the expandable scaffold or other expandable supporting structure span a length in a range from 0.25 mm to 500 mm or more measured in a longitudinal direction, preferably a range from 1 mm to 100 mm, more preferably a range from 10mm to 70mm, and most preferably a range from 10 mm to 40 mm.
  • the expandable scaffold or other expandable supporting structure consists of from 1 ring to 800 rings or more, preferably consist of 25 rings to 650 rings or more, more preferably consist of 50 rings to 500 rings or more, spanning one or more expandable axial segments lengths ranging from 0.2 mm to 50 cm, preferably ranging from 10 mm to 40 cm, more preferably ranging from 15 mm to 25 cm the rings arranged in a longitudinal direction from the distal end of the distal tip to a distal end or to a proximal end, of the aspiration catheter.
  • the expandable scaffold or other expandable supporting structure comprises or consists of a plurality of rings per mm of axial (longitudinal) scaffold or other expandable supporting structure length, ranging from 2 rings/mm to 5 rings/mm of length, preferably consists of from 2.5 rings/mm to 4 rings/mm of length, and more preferably consists of from 3 rings/mm to 4 rings/mm of length, of axial (longitudinal) scaffold length.
  • the expandable supporting structure comprises a plurality of adjacent rings having a gap between the adjacent rings.
  • the gap between adjacent rings has length in a range from 0.0125 mm to 0.25 mm measured in a longitudinal/axial direction, preferably from 0.025 mm to 0.2 mm, and more preferably range from 0.05 mm to 0.17 mm.
  • the axial length of gap (i.e., gap length measured is an axial direction) between adjacent rings may be constant. In other instances, the axial length of gap between adjacent rings may be variable.
  • the length (or axial length) of gaps between at least some adjacent rings range from 0.05mm to 0.2mm.
  • the distal tip has at least 2 ring per mm of axial length, preferably at least 3 rings per mm of length, typically from 1.5 to 5 rings per mm of length, and more typically from 2 to 5 rings per mm of length, or more typically from 3 to 4 rings per mm of length.
  • At least some of the adjacent rings are joined continuously, end-to-end in a helical arrangement.
  • at least some of the adjacent rings are planar, arranged in parallel, and joined by axial links or other means such as attachment points and are not joined end-to-end.
  • the parallel planes may be normal or inclined relative to a longitudinal axis of the distal tip in its as delivered configuration.
  • the adjacent rings may be joined preferably by a single axial link or attachment point, or by no more than two axial links or two attachment points.
  • at least some adjacent rings of the expandable scaffold are joined continuously, end-to-end in a helical pattern or arrangement.
  • At least some adjacent rings of the expandable scaffold are planar, arranged in parallel, and joined by axial links or attachment points joining or connecting structural elements on adjacent rings.
  • the scaffold adjacent rings are not joined continuously end-to-end in a helical arrangement.
  • the parallel planes may be normal or inclined relative to a longitudinal axis of the distal tip in its as delivered configuration.
  • the adjacent rings may be joined preferably by a single axial link or attachment point, or by no more than two axial links or attachment points.
  • At least some adjacent rings of the expandable scaffold are planar, arranged in parallel, and are unconnected to each other. (Unconnected by links, attachment points, or joined end to end in a helical arrangement).
  • the parallel planes may be normal or inclined relative to a longitudinal axis of the distal tip in its as delivered configuration
  • the at least some adjacent rings in this instance are covered by one or more membrane adhering to the unconnected adjacent rings, holding them together, and allowing the at least some adjacent ring to expand from an as delivered configuration to an expanded configuration.
  • At least some of the adjacent rings in the helical and/or planar arrangement may comprise non-linearities.
  • all the adjacent rings in the helical and/or planar arrangement are free from non-linearities.
  • at least some of the adjacent rings have thickness ranging from 0.03 mm to 0.3 mm, preferably ranging from 0.05 mm to 0.25 mm, more preferably ranging from 0.05 mm to 0.2 mm.
  • the malleable metal comprises a metal or metal alloy selected from the group consisting of Cobalt Chrome such as L-605, MP35N, Stellite 6B, ASTM F1537/F799 Alloy 1, ASTM F1537/F799 Alloy 2, Stainless Steel such as 316, 316L, 316LS, 316LVM, 304, 304V, 304L, 304LV, 304LVM, 410, 410L, 410S, 420, 420L, and 420S, Tantalum, Niobium, Tungsten, Molybdenum, Molybdenum, Molybdenum alloys such as Molybdenum-Rhenium where total of the two adds up to 90% to 100% and may include one or more metals such as Boron, Calcium, Chromium, Cobalt, Copper, Gold, Iron, Lead, Magnesium, Manganese, Mercury, Nickel, Niobium, Platinum, Rare Earth metals, Silicon, Silver, Sulfur, Tantal
  • the scaffold or other expandable supporting structure comprises metal or metal alloy selected from the group consisting of Nitinol, Superelastic Nitinol, or the like, or other.
  • the expandable supporting structure is constrained in the as delivered configuration and is released from the constraint to expand the scaffold to the expanded configuration.
  • the expandable membrane comprises one or more of an elastic membrane, and/or inelastic but stretchable membrane, and/or one or more plastically deformable membrane where the membrane may comprise one or more membranes comprising polymers, elastomers, or other as listed previously.
  • the elastic membrane may have isotropic properties. In other instances, the elastic membrane may have anisotropic properties. For example, the membrane may have a higher elasticity in a circumferential direction than in an axial direction.
  • the expandable membrane may comprise an elastic membrane, an inelastic but stretchable membrane, or other type expandable material. Suitable material examples as listed previously.
  • the inelastic membrane may be configured to stretch, or plastically deform as the scaffold or other expandable supporting structure expands. In other instances, an inelastic membrane may be configured to unfold as the as the scaffold or other expandable supporting structure expands.
  • the distal tip may be formed by heat shrinking the tubular membrane on the expandable scaffold or other expandable supporting structure. In other instances, distal tip may be formed by laminating the expandable scaffold or other expandable supporting structure between layers of the tubular membrane. For example, the layers may be bonded to each other so that there is a seal between the layers.
  • the one or more expandable membranes flow and cover at least some side surfaces of the expandable supporting structure structural elements, adhere to the structural elements sufficiently to provide a unified system (an integrated system) in the as delivered configuration and when expanded to an expanded configuration.
  • the polymeric layers on an outer surface of the scaffold and on the inner surface of the scaffold may be bonded to each other and/or adhere to the scaffold structural elements so that there is a seal between the layers and/or adherence to the structural elements providing a unified integrated system expandable from an as delivered configuration to an expanded configuration.
  • the structural elements of the scaffold are not free to move or expand without moving or expanding the expandable membrane adjacent to the structural elements.
  • the layers on an outer scaffold surface and inner scaffold surface may be bonded to each other so that there is a seal between the layers.
  • the layers on an outer scaffold surface and on an inner scaffold surface maybe coupled, attached, and/or adhered to each other substantially eliminating the gaps between the structural elements (or filling the gaps) of the scaffold, and providing a unified expandable scaffold being expandable from an as delivered configuration to an expanded configuration.
  • the one or more layers on an outer surface of the scaffold or the one or more layers on an inner surface of the scaffold are melted or laminated onto the structural elements of the scaffold, eliminating at least in part the gaps between the structural elements and adhering to the structural elements providing the scaffold the ability to expand from an as delivered configuration to an expanded configuration as a unified system.
  • the tubular membrane may consist of at least two membrane segments, where the at least two membrane segments may comprise a single type of material, at least two types of material, or three or more different material types.
  • the at least two membrane segments may cover at least an outer surface of the expandable scaffold or other expandable supporting structure. In some instances, the at least two membrane segments may cover at least an inner surface of the expandable scaffold or other expandable supporting structure. In some instances, the at least two membrane segments cover both an inner surface and an outer surface of the expandable scaffold or other expandable supporting structure, wherein at least one membrane segment of the at least two membrane segments covers an outer surface of the scaffold while at the least the second membrane segment covers an inner surface of the expandable scaffold.
  • the tubular catheter body may be reinforced over at least a portion of its length by a catheter scaffold or other supporting structure, typically a flexible but non-expandable supporting structure.
  • the catheter scaffold or other supporting structure may be formed continuously with the expandable scaffold or other expandable supporting structure.
  • the catheter and supporting scaffold may be patterned from the same tube or bent wire.
  • the catheter scaffold and the expandable scaffold may be formed from one or more bent wires which each span at least portions of the typically non-expandable catheter scaffold and the expandable distal tip scaffold.
  • the expandable scaffolds may further comprise a multiplicity of cantilevered or other supporting elements, each supporting element having a base end and a free end, wherein the base end is attached to one of the radially expandable rings and the free end extends toward or into an adjacent axial and/or circumferential gap.
  • At least some of the plurality of rings may comprise struts joined by bends (crowns) and at least some of the multiplicity of supporting elements have their base ends attached to a strut and at least some of the multiplicity of supporting elements have their base ends attached to a bend (crowns).
  • At least some of the multiplicity of supporting elements may have their base ends attached to an inside surface of the ring, i.e., the inside bend of a crown.
  • At least some of the multiplicity of supporting elements may have their base ends attached to an outside surface of the ring, i.e., an outside surface of a crown, or to the apex of the outside surface of a crown.
  • At least some of the multiplicity of supporting element have a constant width over their distal portions. In some instances, at least some of the multiplicity of supporting element have a constant width over their entire length.
  • At least some of the multiplicity of supporting element have a variable width over their distal portions.
  • At least some of the multiplicity of supporting element have distal tips which extend into an adjacent circumferential, axial, or other gap.
  • At least some of the multiplicity of supporting element have distal tips which terminate flush with the bends that struts join the struts. [0127] In some instances, at least some of the multiplicity of supporting element have distal tips which are recessed between adjacent bends that join the struts.
  • the present invention provides an aspiration catheter comprising a tubular catheter body having a proximal end, a distal end, and a lumen extending along a longitudinal axis.
  • the distal end comprises an expandable distal tip and a central passage where the central passage is typically longitudinally contiguous with the lumen of the tubular catheter body.
  • the distal tip is adapted to expand from a radially contracted or as delivered configuration to a radially expanded configuration in response to a radially outward expansion force applied inside the distal tip, and the distal tip includes a tubular membrane covering (e.g., adhered to, attached to, bonded to, or laminated with) an expandable scaffold or an expandable supporting scaffold.
  • the expandable scaffold or the expandable supporting scaffold comprises a plurality of rings spaced-apart along the longitudinal axis with gaps therebetween (extending between rings) and at least some of the rings comprise circumferentially adjacent cells having bends (such as crowns) configured to unbend (such as to expand) in response to a radially outward expansion force applied inside the distal tip to allow the ring to expand from the radially contracted or as delivered configuration to the radially expanded configuration, wherein the radially expanded configuration is larger than the contracted configuration.
  • at least some adjacent rings of the expandable scaffold or expandable supporting scaffold are joined continuously, end-to-end in a helical arrangement, typically free from axial links or attachments points.
  • the at least some adjacent rings of the expandable scaffold or expandable supporting scaffold have a fixed cell amplitude within each ring. In other instances, the at least some adjacent rings of the expandable scaffold or expandable supporting scaffold have a fixed cell amplitude within the at least some rings. In rare instances, the at least some adjacent rings of the expandable scaffold or expandable supporting scaffold may have a variable cell amplitude within each ring or within the at least some rings.
  • the at least some adjacent rings in this instance have a pitch angle in a range from 70° to 89.9°, or from 75° to 89.9°, usually from 80° to 89.9°, more usually from 84° to 89.75°, and frequently from 85° to 88.5° degrees as patterned, or as delivered, relative to the longitudinal axis of the scaffold or distal tip.
  • the “pitch angle” will be the acute angle (between 0° and 90°) not the obtuse angel (between 90° and 180°) formed by the ring relative to the longitudinal axis of the distal tip of the aspiration catheter.
  • At least some adjacent rings of the expandable scaffold or the expandable supporting scaffold are planar, arranged in parallel, and are joined by one axial link or attachment point joining structural elements on adjacent rings.
  • the at least some adjacent rings are joined by no more than two axial links, by no more than two attachment points j oining structural elements on adjacent rings, or by no more than one link and no more than one attachment point.
  • the parallel planes may be normal or inclined relative to a longitudinal axis of the distal tip in its as delivered configuration.
  • the cells may be arranged in any one or more of a box pattern, diamond pattern, a sinusoidal pattern, serpentine pattern, an omega-wave pattern, a zig-zag pattern, a square wave pattern, a rectangular wave pattern, an undulating pattern, a slotted pattern, open cell pattern, closed cell pattern, a combination of open and closed cell patterns, a combination of patterns, or other, and the like.
  • adjacent and/or non-adjacent rings have crowns that are in-phase or out-of-phase.
  • the cells may comprise struts joined by bends.
  • At least some expandable cells on one or more rings of the expandable scaffold, or at least some expandable cells on at least some rings of the expandable scaffold, or at least some expandable cells on each ring of the expandable scaffold, or the at least some circumferentially adjacent cells of at least some rings of the expandable scaffold, or at least some circumferentially adjacent cells on at least some adjacent rings of the expandable scaffold may, or substantially all cells on the expandable scaffold, or all cells along a length of a scaffold wherein the length is less than the length of the scaffold, or all cells along the length of a scaffold, have a cell period (distance between like points on circumferentially adjacent cells measured in the contracted configuration) in a range from 0.03 mm to 1.3 mm, preferably from 0.04 mm to 0.8 mm, more preferably from 0.05 mm to 0.5 mm, and most preferably from 0.05 mm to 0.15 mm, in the as delivered configuration, or in the as patterned configuration.
  • a cell period distance between like points on circumferentially adjacent
  • Having a small cell period enhances circularity of a ring, or circularity of the plurality of rings, or circularity of the expandable scaffold, thereby enhances navigation of the expandable scaffold into the vasculature without deformation or kinking in the as delivered configuration, and the enhanced circularity resist collapse of the expandable distal tip when expanded to the expanded configuration and a vacuum is applied at a proximal end of the aspiration catheter while the distal tip is engaging a clot (or is plugged). Furthermore, having small cell period increases (or enhances) the aspiration area within the ring, within the plurality of rings, or within the expandable scaffold or expandable distal tip.
  • the circumferentially adjacent cells on at least one ring or on at least some rings (or at least some circumferentially adjacent cells on the same ring, or at least some circumferentially adjacent cells on at least some adjacent rings) of the expandable scaffold, or at least one ring, or at least some rings, or all the rings of the expandable scaffold may have a peak-to-peak amplitude (ring width in the longitudinal/axial direction (the axial width of a ring)) in a range from 0.05 mm to 1.2 mm, preferably from 0.05 mm to 0.8 mm, more preferably from 0.15 mm to 0.5 mm, and most preferably from 0.15 mm to 0.35 mm, in the as delivered configuration or in the as patterned configuration.
  • the cell amplitudes of each cell on the same ring have the same length (is fixed or is constant) in the as delivered configuration or as patterned configuration.
  • at least some adjacent rings have cell or ring amplitude being the same length on the at least some rings.
  • the circumferentially adjacent cells may have a cell period to a (peak to peak axial width of a ring) amplitude range as follows: In one example, a cell period to a (peak to peak axial width of a ring) amplitude range from 0.3 : 1 to 1.6: 1. In other example, a cell period to a (peak to peak axial width of a ring) amplitude range from 0.4: 1 to 1.5: 1.
  • a cell period to a (peak to peak axial width of a ring) amplitude range from 0.5: 1 to 1.3: 1. In yet other example, a cell period to a (peak to peak axial width of a ring) amplitude range from 0.6: 1 to 1.2: 1. In yet other instances, a cell period to a (peak to peak axial width of a ring) amplitude range from 1 : 1 to 1.6: 1. In yet other instances, a cell period to a (peak to peak axial width of a ring) amplitude range from 0.3 : 1 to 1.2: 1, measured in the as delivered configuration or in the as patterned configuration for all the examples.
  • the circumferentially adjacent cells may have a cell period and a (peak to peak axial width of a ring) amplitude each having a length of 0.25mm ⁇ 0.2mm, preferably each having a length of 0.25mm ⁇ 0.15mm, and more preferably each having a length of 0.25mm ⁇ 0.1mm, measured in the as delivered configuration (or measured in the as patterned configuration).
  • each ring may include from 2 cells to 15 cells per mm of circumference, preferably each ring (or at least some rings) may include from 3 cells to 10 cells per mm of circumference, and most preferably each ring (or at least some rings) may include from 4 cells to 9 cells per mm of circumference.
  • At least some rings in the scaffold or other expandable supporting structure may have a ratio of (1) number of bends to (2) circumference, where the ratio is typically in a range from 0.8 per mm to 15 per mm, preferably from 1 per mm to 15 per mm, more preferably from 2 per mm to 15 per mm, more preferably from 3 per mm to 15 per mm and most preferably from 4 per mm to 12 per mm.
  • Supporting structures having cantilevered or other supporting elements will typically have fewer bends per unit length of the ring circumference..
  • the ratio of (1) number of bends to (2) circumference may be constant or variable over at least some rings, over all or a portion of the scaffold or other expandable supporting structure.
  • the rings may span a segment of the distal tip having a length in the distal tip in a range from 0.5 mm to 500 mm or more, usually from 10mm to 100 mm, and more usually from 10 mm to 40 mm, measured in a longitudinal direction.
  • the rings may span a segment of the distal tip having a length in the distal tip in a range from 0.5 mm to 500 mm or more, usually from 10mm to 100 mm, and more usually from 10 mm to 40 mm, measured in a longitudinal direction.
  • the scaffold is composed of one expandable ring spanning a length in the distal tip in a range from 0.1mm to 0.5 mm, usually from 0.15 mm to 0.35 mm, and more usually from 0.15 mm to 0.3 mm, measured in a longitudinal direction.
  • the distal tip may have from 1 to 10 rings per mm of length of the distal tip, usually from 2 to 8 rings per mm of length of the distal tip, more usually from 3 to 5 rings per mm of length of the distal tip.
  • the rings of the expandable supporting structure comprise bends, e.g., crowns, and struts, where the bends have a length measure along their arc and the struts have an axial length, wherein a ratio of the arc length of the bend or crown to the axial length of the strut ranges from 0.2: 1 to 2: 1, preferably from 0.5: 1 to 1.5: 1, and more preferably from 0.75: 1 to 1.25: 1.
  • the arc lengths of crowns and axial lengths of the struts connected to the crowns are each in a range from 0.05 mm to 0.25 mm, preferably from 0.075 mm to 0.225 mm, and more preferably from 0.1 mm to 0.2 mm, preferably being about 0.15 mm, or preferably being 0.15 ⁇ 0.05mm, , for example being 0.15 ⁇ 0.05mm.
  • At least some of the adjacent rings in the expandable distal tip may be formed from a tube or a bent wire and joined continuously in an end-to-end in a helical arrangement.
  • the at least some adjacent rings may be joined at an absolute pitch angle in a range from 70° to 89.9°, or from 75° to 89.9°, usually from 80° to 89.9°, more usually from 84° to 89.75°, and frequently from 85° to 88.5° as patterned or as delivered, relative to the longitudinal axis.
  • the absolute pitch angle may be constant or variable along at least some rings, or along the length of the expandable scaffold (or a long a length of the expandable scaffold wherein the length is shorter than the length of the scaffold or along other expandable supporting structure) or other expandable supporting structure.
  • the absolute pitch angle of at least some adjacent rings maybe constant or variable along the length of the expandable scaffold or other expandable supporting structure.
  • the pitch angles are typically measured in the as patterned configuration. Alternatively, the pitch angles above maybe measured in the as delivered configuration.
  • the at least some adjacent rings are free from links or attachments points between the adjacent rings.
  • the at least some adjacent rings have fixed cell amplitude within each ring or within the at least adjacent rings.
  • at least some adjacent rings may have attachment point or links connecting adjacent rings.
  • at least some adjacent rings may have a variable cell amplitude or a variable ring amplitude within each ring or within the adjacent rings.
  • the adjacent rings may be arranged as separate parallel planes and joined by axial links or joined by other means such as crowns on adjacent rings which are fused/soldered or otherwise joined together (attachment points).
  • the separate parallel planes may be oriented perpendicularly or at an angle relative to a longitudinal axis of the scaffold or other expandable supporting structure when straightened.
  • the separate adjacent rings are not joined together by links or by other means but are held together by one or more expandable membrane containing, covering, and/or embedding the separate rings.
  • the cells may comprise a malleable metal or metal alloy configured to plastically deform.
  • the malleable metal may comprise a metal or metal alloy as identified previously in this application.
  • the radially contracted configuration of the scaffold or other expandable supporting structure and/or the distal tip may have a maximum diameter in a range from 0.5 mm to 30 mm, usually from 1.3 mm to 5.5 mm, and the radially expanded configuration may have a minimum diameter in a range from 1 mm to 40 mm, usually from 2 mm to 5.5mm.
  • the distal tip may be configured to expand from an initial cylindrical shape to an enlarged cylindrical configuration in response to the radially outward expansion force applied within the distal tip.
  • distal tip may be configured to expand from an initial cylindrical shape to an enlarged conical configuration in response to the radially outward expansion force applied within (or applied from inside) the distal tip.
  • circumferentially adjacent cells in at least some of rings in the distal tip may have round, oval, oblong, flat, or substantially flat outer and/or inner surfaces which define “facets” in a polygonal structure.
  • the ring may have a first radius from an axial center line of the ring to the circumferential center of each facet and a second radius from an axial center line of the ring to the a circumferential edge of each facet where the length of the first radius is from 97% to 99.9% of the length of the second radius, preferably being from 98% to 99.7%, more preferably being from 98.5% to 99.5%, and most preferably being from 99% to 99.5%, in the expanded configuration.
  • the expandable distal tip with one or more of the following: enlarged inner lumen configuration (or maximum inner lumen configuration), enhanced aspiration lumen area, maximize the aspiration lumen area in the expanded configuration, resist collapse in the expanded configuration under vacuum when the distal tip is engaging a clot (or blocked or plugged with clot or other substances, enhance deliverability of the aspiration catheter distal tip, and enhance deformation resistance or kink resistance of the expandable distal tip in the as delivered configuration when navigating the vasculature.
  • the expandable tip in the expanded configuration has a “circularity” (as defined below with respect to FIG.
  • the circularity of the expandable tip in the expanded configuration is greater than 97%, preferably greater than 98%, more preferably greater than 98.5%, and most preferably greater than 90%.
  • the circularity of the expandable distal tip refers to the inner lumen configuration. Alternatively, the circularity of the expandable distal tip measuring the outer circumference of the distal tip.
  • the tubular catheter body may have a length from the proximal end to the distal end in a range from 50 cm to 200 cm, an outer diameter in a range from 0.5 mm to 30 mm, and an inner lumen diameter from 0.25 mm to 25 mm.
  • the expandable distal tip length ranges from 0.5 mm to 50cm.
  • the expandable distal tip length is the same as the distal end length.
  • the expandable distal tip comprises substantially the entire length of the catheter tubular body.
  • the expandable distal tip is composed of an expandable scaffold (or expandable supporting scaffold) covered with or embedded within one or more polymeric material, wherein the expandable scaffold comprises one circumferential ring, the one ring comprises a plurality of struts joined by crowns, and wherein the ring is expandable from an as delivered configuration to an expanded configuration, the ring resist collapse when a vacuum is applied at a proximal end of the aspiration lumen and the distal end of the distal tip is opposed to a clot or plugged.
  • the expandable scaffold comprises 2, 3, 4, or 5 circumferential rings.
  • the expandable distal tips may further comprise a multiplicity of supporting elements, where each supporting element may have a base end and a free end and where the base end is attached to one of the radially expandable rings and the free end extends towards or extends into an adjacent gap in an axial and/or circumferential direction to the distal tip.
  • each supporting element may have a base end and a free end and where the base end is attached to one of the radially expandable rings and the free end extends towards or extends into an adjacent gap in an axial and/or circumferential direction to the distal tip.
  • at least some of the plurality of rings may comprise struts joined by bends and at least some of the multiplicity of supporting elements may have their base ends attached to a strut and/or at least some of the multiplicity of supporting elements may have their base ends attached to a bend.
  • At least some of the multiplicity of supporting elements may have their base ends attached to an inside surface of the ring (or the rings ring’s structural elements) and/or attached to an outside surface of the ring (or the ring’s structural elements).
  • at least some of the multiplicity of supporting elements may have a constant width over their distal portions or along their entire length.
  • at least some of the multiplicity of supporting element may have a variable width over their distal portions or along their length.
  • at least some of the multiplicity of supporting elements may have a larger width at their base and a constant width along the remaining length of the supporting elements.
  • the width of the supporting elements is larger than the width of an adjacent struts, crown, or ring segment. Having larger supporting elements width that adjacent structural elements allow contraction of the expandable scaffold or other expandable supporting structure after expansion of the scaffold to an expanded configuration when the scaffold is withdrawn into a guiding catheter having an inner lumen smaller than the expanded configuration of the expandable scaffold.
  • At least some of the multiplicity of supporting elements may have distal tips which extend toward and/or into the adjacent circumferential and/or axial gap. [0154] In some instances, at least some of the multiplicity of supporting elements may have distal tips which terminate flush with adjacent bend or crowns that join the struts.
  • At least some of the multiplicity of supporting elements have distal tips which are recessed between adjacent bends that join the struts in the as delivered configuration and wherein the supporting elements project further towards or further into an adjacent gap.
  • the present invention provides methods for aspirating clot from a patient’s vasculature comprising positioning a distal tip of any one of the aspiration catheters described herein in the patient’s vasculature at a region of clot.
  • the distal tip is expanded to its radially expanded configuration, or to a radially expanded configuration from an as delivered configuration, to engage a vascular wall adjacent the region of clot, or to engage a clot, and a negative pressure is applied to a proximal end of the lumen in the catheter body to aspirate the clot into the central passage of the expanded expandable supporting structure (the aspiration lumen).
  • the expanded configuration has a suction force larger than the as delivered configuration under the same applied vacuum.
  • the suction force in the expanded configuration is larger by a range from 1.1 to 10 times, preferably larger by a range from 1.5 to 6 times, more preferably larger by a range from 1.8 to 6 times the suction force of the as delivered configuration.
  • At least a portion of the expandable scaffold or other expandable supporting structure remains at least partially unexpanded after expansion of another portion of the expandable scaffold.
  • the at least partially unexpended portion may have a variety of shapes such as cone shape, oval shape, oblong shape, flat shape, or other shapes.
  • at least one segment of the expandable scaffold or other expandable supporting structure comprises remains unexpanded after expansion of another adjacent segment of the expandable scaffold or other expandable supporting structure to the expanded configuration.
  • the present invention provides a method for aspirating clot from a patient’s vasculature comprising positioning a distal tip of any one of the aspiration catheters described herein in the patient’s vasculature at a region of clot. At least a segment of the distal tip is expanded to its radially expanded configuration from an as delivered configuration (contracted configuration) to engage a vascular wall adjacent to the region of clot, or to engage a clot, and a negative pressure is applied to a proximal end of the lumen in the catheter body to aspirate the clot into the central passage of the expanded expandable structure.
  • the clot is aspirated in the contracted (as delivered) configuration without expanding the distal tip to the expanded configuration.
  • a segment or other portion of the expandable scaffold or other expandable supporting structure remains at least partially unexpanded after expansion of another portion of the expandable scaffold.
  • the present invention provides an aspiration catheter comprising a tubular catheter body having a proximal end, a distal end, and a lumen extending along a longitudinal axis.
  • An expandable coil comprising successive helical turns is disposed along a longitudinal axis, where the expandable coil comprises undulating bends and struts and the successive turns having a gap therebetween, wherein the successive turns are inclined at an acute pitch angle relative to the longitudinal axis.
  • a jacket is disposed about the expandable coil.
  • the acute pitch angle ranges from 70° to 89.9°, usually from 80° to 89.75°, and more usually from 82° to 89.75° degrees, relative to the longitudinal axis, in the as patterned or as delivered configurations.
  • at least some successive turns are free from links or attachment points joining the adjacent turns.
  • at least some adjacent turns have fixed cell amplitudes within each turn or within the at least some adjacent turns.
  • the expandable scaffold or other expandable supporting structure is composed of an expandable coil wherein the expandable coil comprises a plurality of adjacent expandable rings joined continuously, end-to-end in a helical arrangement, wherein each ring comprises structural elements comprising struts joined by crowns, and wherein the expandable coils have an acute pitch angle ranging from 70° to 89.9°, preferably ranging from 80° to 89° degrees, relative to the longitudinal axis as patterned or as delivered.
  • the expandable coil is expanded from an as delivered configuration or a contracted configuration to an expanded configuration by an expandable supporting structure radially expanded in an interior of the expandable coil such as a balloon catheter, wherein the expandable coil is the to be balloon expandable.
  • the expandable coil may be configured to be expanded by an expandable supporting structure radially expanded in an interior of the expandable coil.
  • the expandable coil may be balloon expandable.
  • the coil may be formed at least in part from a malleable metal or metal alloy. In some other examples, the coil may be formed from a malleable metal or metal alloy.
  • the coil maybe formed from a shape memory metal or shape memory alloy, wherein the expandable distal tip is constraint in the as delivered configuration and is released to expand to the larger expanded configuration.
  • shape memory alloys include nickel titanium alloy, or other.
  • at least a proximal portion of the tubular catheter body may be non-expandable.
  • At least a proximal portion of the tubular catheter body may be radially expandable.
  • the expandable coil may be attached to a reinforcement member in a proximal segment of the catheter body.
  • the expandable coil and the reinforcement member may be formed from a continuous wire or tube.
  • the adjacent rings may be joined at an acute pitch angle in a range from 70° to 89.9°, preferably range from 80° to 89.9°, more preferably range from 85° to 89° degrees, and most preferably range from 86° to 89° relative to the longitudinal axis in the as patterned configuration or in the as delivered configuration.
  • the expandable coil may be attached to distal end of the tubular catheter body, incorporated within the distal end of the tubular catheter body, or coupled to the distal end of the tubular catheter body. In some other instances, the expandable coil may extend from the distal end of the tubular catheter body to a proximal end, or to the proximal end of the tubular catheter body. The expandable coil in some instances maybe attached to a proximal end of the tubular catheter body.
  • expandable coil is embedded or laminated in the expandable membrane or embedded or laminated in the tubular catheter body.
  • the expandable coil may have a crimped delivery configuration and an expanded deployed configuration.
  • the crimped delivery configuration of the expandable coil has a maximum outer diameter in a range from 0.5 mm to 30 mm and the expanded deployed configuration has a maximum outer diameter in a range from 1.5 mm to 40 mm.
  • FIG. 1 illustrates an aspiration catheter system comprising an aspiration catheter body and a separate distal tip structure constructed in accordance with the principles of the present invention.
  • FIGS. 2A to 2E illustrate use of the aspiration catheter system of FIG. 1 in extracting clot from a patient’s vasculature.
  • FIG. 3 illustrates an aspiration catheter system comprising an aspiration catheter body having an integrated distal tip structure with a rapid-exchange guidewire port constructed in accordance with the principles of the present invention.
  • FIGS. 4 A to 4D illustrate use of the aspiration catheter system of FIG. 3 in extracting clot from a patient’s vasculature.
  • FIG. 5 illustrates an alternative construction of an aspiration catheter having a plurality of expandable segments constructed in accordance with the principles of the present invention.
  • FIG. 6 illustrates an alternative construction of an aspiration catheter having a separate guidewire tube constructed in accordance with the principles of the present invention.
  • FIGS. 7A to 7D are cross-sectional views taken along line 7-7 of FIG. 6.
  • FIG. 8A is a detailed view of an example of an expandable tip suitable for use in the aspiration catheter of the system of FIG. 1 shown in a non-expanded configuration (or in as delivered configuration) with a portion of a cover (or laminated) membrane removed or broken away to expose an expandable supporting scaffold or other expandable supporting structure.
  • FIG. 8B is a “rolled out” view of an example of the expandable supporting scaffold of the tip of FIG. 8 A.
  • FIG. 8C is a detailed view of an adjacent pair of circumferentially expandable supporting rings of the expandable scaffold of FIG.8 A showing supporting elements and a link joining the adjacent rings.
  • FIGS. 9A to 9D illustrate the supporting scaffolds of FIGS. 8A to 8C shown in alternative expanded configurations.
  • FIG. 10A is a “rolled out” view example of a supporting scaffold or other expandable supporting structure having helically arranged circumferential supporting rings constructed in accordance with the principles of the present invention.
  • FIG. 10B is a detailed view of adjacent circumferential supporting rings of the expandable distal tip of the supporting scaffold of FIG. 4A.
  • FIG. 10C is an image of the supporting cell space of FIG. 4 A incorporated into polymeric tubular envelope (one or more membranes) in an unexpanded configuration (as delivered configuration).
  • FIG. 10D is an image of the supporting scaffold and polymeric tubular envelope (one or more membranes) of FIG. 4C shown after the integrated membranes/expandable scaffold were radially expanded by a balloon from an as delivered configuration to an expanded configuration.
  • FIG. 11 A is a “rolled out” view of another example of a supporting scaffold having helically arranged circumferential supporting rings constructed in accordance with the principles of the present invention.
  • FIG. 1 IB is a detailed view of adjacent circumferential supporting rings of the expandable distal tip of the supporting scaffold of FIG. 11 A.
  • FIG. 12A is a “rolled out” view of a further example of a supporting scaffold having helically arranged circumferential supporting rings constructed in accordance with the principles of the present invention.
  • FIG. 12B is a detailed view adjacent circumferential supporting rings of the expandable distal tip of the supporting scaffold of FIG. 12A.
  • FIGS. 13A to 13AR-2 illustrate a variety of alternative examples of geometries, scaffold designs, and connection locations and shapes for the supporting elements of the present invention.
  • FIG. 14 is a “rolled out” view of a further example of a supporting scaffold having adjacently linked circumferential supporting rings with differing frequency of number of crowns, gap widths, cells periods, cells amplitudes and differently configured examples of supporting elements constructed in accordance with the principles of the present invention.
  • FIG. 15A is a “rolled out” view of an alternative example of a supporting scaffold having helically arranged circumferential supporting rings free from supporting elements constructed in accordance with the principles of the present invention.
  • FIG. 15B is a detailed view of adjacent circumferential supporting rings of the expandable distal tip of the supporting scaffold of FIG. 15 A.
  • FIG. 15C illustrates an alternative example of the supporting scaffold of the present invention having discrete supporting pads (or islands) located between struts of a serpentine supporting ring.
  • FIG. 16A is a detailed view of an expandable distal tip of an alternative example of the aspiration catheter of the present invention having supporting scaffold comprising a plurality of rings shown in a non-expanded configuration with a portion of a cover membrane removed or broken away.
  • FIG. 16B is a “rolled out” view of the supporting scaffold of the expandable distal tip of the aspiration catheter of the system of FIG. 16A showing the transition from an expandable scaffold of the distal tip to a non-expandable supporting scaffold formed as a helical coil in a body of the aspiration catheter.
  • FIG. 16C is a detailed view of the individual cells of the supporting scaffold of the expandable distal tip of the aspiration catheter of the system of FIG. 16A showing recessed supporting elements and a compacted pattern configuration in the as patterned configuration (or as delivered configuration).
  • FIG. 16C also shows the arc length of crowns being about the same length as the axial length of struts.
  • FIG. 16D is an enlarged “rolled out” view of the supporting scaffold of the expandable distal tip of the aspiration catheter of the system of FIG. 16A showing details of a flush distal termination ring.
  • FIGS. 16E and 16F illustrate recessed and protruding cantilevered supporting elements of the present invention.
  • FIGS. 16G and 16H illustrate exemplary helical supporting structures comprising two and three nested continuous helical rings, respectively.
  • FIGS. 17A and 17B illustrate how the “pitch angle” as referred to herein can be determined as an acute angle.
  • FIGS. 17C-17E illustrate distal tip supporting scaffolds having varying pitch angles and varying gap lengths between rings.
  • FIGS. 18A-18C are detailed exemplary views illustrating different bending patterns that can be utilized in the radially expandable distal tip rings of the present invention.
  • FIGS. 18D and 18E are side and perspective views of radially expandable distal tip rings of the present invention having a repeating omega-shaped cell pattern.
  • FIG. 19 illustrates the how the faceted outer surface of the radially expandable distal tip rings of the present invention approaches a circular perimeter as a measure of circularity.
  • FIG. 20 identifies various characteristics that can be used to define the rings of a scaffold or structure of a helical, radially expandable distal tip of the present invention.
  • FIGS. 21 A to 21C are side, perspective, and “rolled-out” views of an expandable scaffold comprising a plurality of transversely oriented, axially linked (or joined) expandable rings.
  • FIG. 22 identifies various characteristics that can be used to define the structure of an expandable scaffold comprising a plurality of transversely oriented, axially linked (or joined) expandable rings, such as that shown in FIGS. 18A-18C.
  • FIGS. 23A and 23B are side and “rolled-out” views of an expandable scaffold comprising a plurality of parallel, axially linked (or joined) expandable rings which are inclined relative to a longitudinal axis of the scaffold.
  • FIG. 24 is a “rolled-out” view of an expandable scaffold having segment with cells aligned in phase and out-of-phase.
  • FIG. 25 is a “rolled-out” view of an expandable scaffold comprising a plurality of rings with gaps therebetween having varying lengths.
  • FIG. 26A is a “rolled-out” view of an expandable scaffold comprising a plurality of rings with gaps therebetween arranged in a helical pattern.
  • FIG. 26B is a detailed exemplary view of the rings of FIG. 26 A showing that each ring has a serpentine pattern.
  • FIGS. 26C to 26E are rotated side views of the expandable scaffold of FIG. 26A.
  • FIG. 27A is a “rolled-out” view of an expandable scaffold comprising a plurality of rings with gaps therebetween arranged in a helical pattern where individual rings have a first curved shape in the rolled-out pattern.
  • FIG. 27B is a detailed view of the rings of FIG. 27A showing that each ring has a serpentine pattern.
  • FIGS. 27C to 27E are rotated side views of the expandable scaffold of FIG. 27A.
  • FIG. 28A is a “rolled-out” view of an expandable scaffold comprising a plurality of rings with gaps therebetween arranged in a helical pattern where individual rings have a second curved shape in the rolled-out pattern.
  • FIG. 28B is a detailed exemplary view of the rings of FIG. 28 A showing that each ring has a serpentine pattern.
  • FIGS. 28C to 28E are rotated side views of the expandable scaffold of FIG. 28A.
  • FIG. 29 is “rolled-out” view of a ring pattern comprising S-shaped expandable elements joined by non-extendable circumferential links shown prior to expansion.
  • FIG. 30 is “rolled-out” view of a ring pattern comprising a bent wire having integrated cantilevered supporting elements.
  • FIGS. 31A and 3 IB are “rolled-out” views of a closed-cell box ring pattern shown in its non-expanded and expanded configurations, respectively.
  • FIGS. 32A and 32B are “rolled-out” views of a closed-cell box ring pattern shown in its non-expanded and expanded configurations, respectively, further comprising cantilevered supporting elements recessed between circumferentially adjacent box elements in the non-expanded configuration.
  • FIGS. 33A and 33B are “rolled-out” views of an alternative closed-cell box ring pattern shown in its non-expanded and expanded configurations, respectively, further comprising cantilevered supporting elements recessed between circumferentially adjacent box elements in the non-expanded configuration.
  • FIGS. 34A to 34C illustrate an exemplary method for embedding a radially expandable supporting scaffold or other structure in a polymer membrane.
  • FIG. 35 is a cross-sectional view of a distal tip region fabricated by the method of FIGS. 31 A to 31C, shown in a radially expanded configuration.
  • an aspiration catheter comprises at least two separate components that can be assembled in situ to form a fully functional aspiration catheter.
  • a first component comprises a distal tip assembly and the second component comprises a catheter body, e.g., a guide catheter or sheath, having a central lumen that receives the distal tip assembly.
  • the distal tip assembly comprises an expandable segment carried at the distal end of an elongate member, such as a hypo-tube or other push rod.
  • the expandable segment has a central passage therethrough which serves several purposes, including serving as a short guidewire lumen as the distal tip assembly is advanced through the central lumen of the catheter body.
  • the expandable distal tip typically is configured to be radially expanded to form a funnel-type tip to engage the clot to be aspirated and typically comprises one or more expandable membranes covering or otherwise coupled to an outer surface and/or an inner surface of an expandable scaffold.
  • the expandable distal segment is further configured so that when expanded, a proximal portion of the expanded portion will overlap with an inner, distal surface of the separate catheter body, providing a fluid seal therebetween.
  • the length of the overlap segment can vary ranging from 5 mm to 25 cm, preferably ranging from 1 cm to 10 cm.
  • the lumen of the catheter body e.g., guiding catheter or guiding sheath, thus provides a contiguous lumen with the inner passage of expandable distal segment, providing a continuous aspiration lumen extending from the distal end of the expandable segment to the proximal end of the catheter body to enable clot extraction when a vacuum is applied at the proximal end of the catheter body and the distal end of the expanded segment is engaging the clot.
  • a clot aspiration system 10 for removing clot from a patient’s vasculature, typically the cerebral vasculature comprises (1) a catheter body 12 having a distal end 14 and a proximal end 16, and (2) a distal tip structure 20 having an expandable segment 22 coupled, disposed, or attached to or embedded within a distal end 28 of an elongate member such as rod 26.
  • the distal tip structure 20 is formed separately from the catheter body 12 and, the distal tip structure and the catheter body are configured to be assembled in situ to form a functioning aspiration catheter, as described in more detail below.
  • the catheter body 12 has an aspiration lumen 18 extending from its distal end 14 to the proximal hub 16, and the proximal hub is configured to attach to a vacuum or negative pressure source (not shown) of the type typically found in a hospital or other medical care facility.
  • a vacuum or negative pressure source not shown
  • clot can be aspirated through the distal opening 32 of the expanded distal tip structure 20 when the catheter is fully assembled and deployed in a patient’s vasculature, as described in more detail below.
  • the expandable segment 22 of the distal tip structure 20 has an open, a central passage (not shown) with a proximal opening 30 and a distal opening 32.
  • the central passage both allows the distal tip structure 20 to be advanced over a guidewire and receives a balloon or other expandable member to allow radial expansion to form the funnel-like shape that facilitates clot extraction.
  • the rod 26 of the distal tip structure 20 further comprises a proximal hub 28 to permit manual advancement and retraction of the expandable segment within the limen 18 of the catheter body.
  • the expandable segment 22 is illustrated in its radially constricted or “low-profile” configuration in a full line and in its radially expanded configuration in broken line.
  • FIGS. 2 A to 2E A method for clot extraction will now be described with reference to FIGS. 2 A to 2E.
  • the distal end 14 of the catheter body 12, typically a guiding catheter or sheath is advanced over a guidewire GW through a patient’s artery AR to a location proximate a region of clot CL, as shown in FIG. 2A.
  • the distal tip structure 20 is advanced through the lumen 18 of the catheter body 22 over the guidewire GW in a rapid exchange or monorail manner with the guidewire passing through the unexpanded central portion of the expandable segment 22.
  • a distal portion of the expandable segment 22 is positioned distally beyond the distal end 14 of the catheter body 12 with a shorter proximal portion of the expandable segment remaining within the distal lumen of the catheter body, as shown in FIG. 2B.
  • the expansion catheter 40 is then introduced over the guidewire GW so that it fully occupies the internal passage of the expandable member 22, as shown in FIGS. 2C and 2D.
  • the balloon or other expandable structure 44 After the balloon or other expandable structure 44 has been properly positioned, it is inflated to expand the expandable member 22 with an unconstrained distal portion of the expandable segment forming a funnel-like tip at the distal end of 14 of the catheter body 12. Conversely, expansion of a proximal portion of the expandable member 22 is constrained by the fixed diameter of the distal end 14 of the catheter body 12, so that there is an overlapping region 54 which is tightly sealed against an inner surface of the lumen of the catheter body, preventing or inhibition fluid leakage and allowing a negative pressure to be applied to the expanded segment 22 from the hub 16 of the catheter body.
  • the present invention provides an aspiration catheter having a side guidewire report (formed through a wall of the aspiration catheter body) which is configured to be allow the catheter to be introduced over a guidewire in a rapid exchange or monorail manner.
  • a guidewire may be inserted into a distal port of the aspiration catheter and exit through the side guidewire port at a pre-selected distance, typically 10 cm to 25 cm, from the distal tip of the aspiration catheter.
  • the aspiration catheter will typically be delivered through a separate guiding catheter or sheath where the side guidewire port remains retracted within a distal portion of the guiding catheter or sheath while a negative pressure is applied to the aspiration catheter to extract clot.
  • the side guidewire port will typically comprise an overlapping segment, such as a sleeve or lumen, separate from the aspiration lumen.
  • the side guidewire port will typically have a cross-sectional area which substantially smaller than that of the aspiration lumen, to provide a sufficient fluid seal to maintain the vacuum which is applied at a proximal end of the aspiration catheter and a clot engages the expandable distal end of the aspiration catheter,
  • the overlap or separate lumen we'll typically have a length in a range from 1 cm to 10 cm.
  • a guide member of other structure may be provided in a distal portion of the aspiration lumen to guide the guidewire when inserted into the distal end of the aspiration lumen to exit through the side guidewire port.
  • the guide member will usually be removeable.
  • the guide member may be formed form metallic or polymeric material and may have a round, D-shaped, or other configuration to guide the guidewire into the side guidewire port.
  • the guidewire remains in place during vacuum, while in another example the guidewire is removed, and if necessary, another guidewire is advanced from the proximal end of the aspiration catheter to the distal end of the spiration catheter or beyond.
  • an aspiration catheter system 100 comprises a guiding catheter or sheath 112, an aspiration catheter 120, and a tip expansion catheter 140.
  • the guiding catheter or sheath 112 comprises a simple tubular structure with an open distal port or end 114, a proximal hub 116, and an open lumen therebetween.
  • the guiding catheter or sheath 112 may have a conventional construction and the lumen 118 of the guiding sheath or catheter 112 will be configured to receive the aspiration catheter 120 to facilitate deployment.
  • the aspiration catheter 120 comprises a tubular shaft 126, a balloon or other expandable segment 122 at a distal end 124 of the tubular shaft, and a hub 130 at a proximal end of the tubular shaft.
  • An aspiration lumen 128 extends form the distal end 124 to the proximal hub 130 and is configured to receive clot from the expandable segment 122 when deployed by applying a vacuum or negative pressure thorough the proximal hub.
  • a side guidewire port 132 is formed a short distance from the distal end 124 of the catheter shaft 126, typically from 5 cm to 50 cm, usually 10 cm to 25 cm, proximal of the distal end 124, where side guidewire port 132 will be configured to seal against fluid intrusion, either before or after the guidewire is removed, while a negative pressure is being applied to the aspiration lumen 128 in order to extract clot.
  • the side guidewire port 132 may comprise a short sealing tube or lumen 134 formed along a side of the shaft 126.
  • the side guide wire port 132 and/or sealing tube 134 will be configured to collapse in response to a negative pressure being applied within the aspiration moment.
  • side guide wire port 132 and/or sealing tube 134 will have a length and/or diameter sufficient to provide a relatively high fluid resistance to inhibit fluid flow into the aspiration lumen in response to a negative pressure, either with or without the guidewire present.
  • the distal tip structure expansion catheter 140 is typically a balloon catheter where the distal expansion member 144 typically comprises a balloon disposed at a distal end of a shaft 142.
  • a proximal hub 146 is attached to a proximal end of the shaft 142 and includes a first luer connector 148 and a second luer connector 150.
  • the first luer connector 148 opens to a guidewire lumen (not shown) which extends the entire length of shaft 142 and allows the catheter shaft 142 to be advanced over a guidewire or a microcatheter to target location in the patient’s cerebral or other vasculature. While illustrated as having an “over the wire design,” the tip expansion catheter 140 could also have a rapid-exchange or monorail design.
  • the second luer connector 150 opens to a balloon inflation lumen (not shown) in the shaft 142 which allow inflation of the balloon to in turn expand the expandable segment 122 of the aspiration catheter 120 proximate a target clot in the patient’s vasculature, as will be described in more detail below.
  • FIGS. 4 A to 4D use of the clot aspiration system 100 for extracting cloth CL from a patient's arterial vasculature AR will be described.
  • the distal end 114 of the catheter body 112, typically a guiding catheter or sheath, is advanced over a guidewire GW through a patient’s artery AR to a location proximate a region of clot CL, as shown in FIG. 4A.
  • distal end 124 of the aspiration catheter 120 is advanced through the lumen 118 of the catheter body 112 over the guidewire GW in a rapid exchange or monorail manner with the guidewire passing through the side guide wire port 132 and/or sealing tube 134 to position the unexpanded expandable segment 122 proximate the clot CL.
  • the tip expansion catheter 140 may then be introduced through the lumen 128 of the aspiration catheter 120, optionally over a second guidewire (not shown).
  • the first guidewire may or may not have been withdrawn but is not shown in FIG. 4C for ease of illustration.
  • the balloon or other expandable structure 144 fully occupies the internal passage of the expandable member 122 and may then be inflated to expand and deploy the expandable segment 122, as shown in FIG. 4D, and the aspiration catheter is then ready for clot extraction by applying a vacuum or negative pressure to the proximal hub 130.
  • FIG 5 an aspiration catheter 160 having a plurality of expandable segments is illustrated.
  • a first expandable segment 166 may be disposed at a distal end of a catheter shaft having a proximal hub 164.
  • At least one additional, second expandable segment 168 is located on the shaft 162 proximally of the first expandable segment 164.
  • the second expandable segment 168 may be expanded (as shown in broken line) in a patient vasculature, typically distal to a guiding catheter or sheath, to inhibit or reduce back blood flow or minimizes blood loss when a vacuum is attached at a proximal end of the aspiration catheter 160 and a clot engages the distal end.
  • the second expandable segment 168 may overlap the distal end of a guiding catheter or sheath to provide a seal as described with respect to FIGS. 2 A to 2E.
  • an aspiration catheter 180 comprises a catheter body 182 having a proximal hub 184, a distal expandable segment 186, and an aspiration lumen 185 extending therebetween.
  • a separate guidewire tube or lumen 188 is provide over and/or in a distal length of the catheter body 182, typically over a length from 5 cm to 50 cm, usually from 10 cm to 25 cm.
  • the separate guidewire tube or lumen 188 has a distal port 190 and a proximal port 192 and is illustrated as having the distal port flush with a distal end 104 of the expandable segment 186.
  • the distal port 190 of the separate guidewire tube or lumen 188 may be disposed distally of a distal end 194 of the expandable segment 186, for example being located proximally of a proximal end 196 the expandable segment so that there is no overlap.
  • the separate guidewire tube or lumen 188 may be shorter than the expandable segment 186 of the aspiration catheter 180 (ending proximally to the distal end of the aspiration catheter) or may have the same length as the distal segment length.
  • FIGS. 7A to 7D shows various cross-sections of the separate guidewire tube or lumen 188.
  • the aspiration catheters 180 allow for both a rapid exchange and an over-the-wire deployment catheter, providing the physician with an option.
  • the aspiration catheter 180 may be advanced over a guidewire GW received in the separate guidewire tube or lumen 188, entering port 190 and exiting port 192, as illustrated in FIG. 6.
  • the aspiration catheter 180 may be advanced over a guidewire received in the aspiration lumen 185 in an over-the-wire manner.
  • a vacuum may be applied to hub 184 at the proximal end of the aspiration catheter 180 to extract the clot.
  • the expandable distal tip 218 includes both an expandable supporting scaffold 238 and an expandable membrane 240.
  • the expandable membrane 240 will typically comprise one or more of an elastic or stretchable inelastic polymeric membrane having the supporting scaffold 238 embedded or laminated therein covering the scaffold.
  • the supporting membrane(s) may flow into, protrude, or otherwise adhere to the supporting scaffold structural elements providing an integrated expandable scaffold membrane system.
  • the supporting scaffold 238 will typically comprise a metal or metal alloy, typically formed from a malleable metal or metal alloy, the scaffold is configured for balloon expansion but in other cases could be configured for self-expansion after release from constraint.
  • the supporting scaffold 238 includes a plurality of radially expandable circumferential supporting rings 242, and each ring is separated from an adjacent ring by a gap.
  • the rings will usually comprise undulating, such as serpentine, box, or zig-zag pattern including struts 248 joined by crowns 250 where adjacent rings 242 may be connected by axial one link 246.
  • the supporting scaffold 238 shows perpendicular rings having about 90° relative to the longitudinal axis, the supporting scaffold 238 may alternatively be formed from a plurality of rings having an acute pitch angle, the pitch angle preferably ranges from 70° to 89.9°, relative to the longitudinal axis in the as patterned or as delivered configuration (not shown).
  • adjacent rings are joined by one link, or no more than one link, or no more than two links (not shown).
  • Links can have a variety of shapes such as offset linear (as shown) or other types of shapes linear or non-linear such as U, M, Z, S, or other shapes.
  • at least some adjacent rings are not joined together but are held together by a membrane covering, shrunk onto, coated over, or melted over, the at least some rings, allowing the rings to be held together in the as delivered configuration and to expand from an as delivered configuration to an expanded configuration.
  • adjacent rings are typically joined by one or more links, alternatively, sometimes structural elements on adjacent rings are soldered or fused or attached together joining the adjacent rings in one or more location.
  • the supporting scaffold 238 may be formed from an expandable coil wherein the expandable coil comprises a plurality of adjacent expandable rings (or turns) joined continuously, end-to-end in a helical arrangement, each ring comprises structural elements comprising supporting elements and struts joined by crowns, and the expandable coils have an acute pitch angle ranging from 70° to 89.9°, preferably ranging from 80° to 89°, relative to the longitudinal axis in the as patterned or as delivered configuration.
  • the expandable rings of the expandable coil of the supporting scaffold are joined continuously, end-to-end in a helical arrangement, and are typically not joined otherwise (such as by links or by attaching structural elements or attachment points on adjacent rings).
  • At least some rings of the expandable coil may be joined by one or more links or joined by attaching structural elements on adjacent rings, typically on rings at a proximal end of expandable segment 22 shown in of FIG. 1 to provide support.
  • the expandable coil is expanded from an as delivered configuration or a contracted configuration to an expanded configuration by an expandable supporting structure radially expanded in an interior of the expandable coil such as a balloon catheter, wherein the expandable coil is the to be balloon expandable.
  • the supporting scaffold may be formed from a bent wire forming a plurality of adjacent turns joined continuously, end-to-end in a helical arrangement.
  • the expandable coil may be formed from a tubular body and patterned into the expandable coil comprising a plurality of circumferentially expandable rings.
  • there is a gap between at least some rings of an expandable scaffold preferably there is a gap between all adjacent rings of an expandable scaffold.
  • gaps between adjacent rings are typically fixed (FIG. 8A, 8B, and 8C) , but in some instances gaps may have variable axial lengths (not shown).
  • supporting elements 252 of the expandable scaffold 238 are located between adjacent pairs of struts 248 and have a base end 256 attached to an inner radius of the crown 250 which joins the struts with adjacent supporting members facing in opposite axial directions.
  • the supporting elements 252 strengthen a region of the expandable membrane 240 which spans (extends across) the struts 248.
  • supporting elements 252 length in this preferred example is equal to or shorter than the ring period, thereby not extending into the gap region between adjacent rings (as shown). This enhances deliverability of the scaffold and strengthens the region of the expandable membrane.
  • the supporting elements 252 length is longer than /i the length of an adjacent strut and the length is equal to or shorter than the adjacent ring period (as shown). This provides a balance between strengthening the region of the expandable membrane and enhances deliverability of the scaffold.
  • the supporting elements 252 in this example have an axial length, a base, and a free end, wherein the free end terminate at or prior to the start of the gap region between rings (as shown). In yet rare instances, the supporting elements length may extend beyond the peak of an adjacent crown, extending into the gap region between rings (not shown). In this preferred example, the supporting elements 252 within each ring have the same length.
  • the supporting elements 252 within at least some rings, or within the entire length of the scaffold have the same length (as shown). However, supporting elements within one ring may have different lengths (not shown), or supporting elements on adjacent rings may have different lengths (not shown), or supporting elements on at least some rings are different (not shown).
  • the width of the supporting elements 252 is the same within each ring and also within a plurality of rings (as shown). However, width of the supporting elements may be different within one ring or within a plurality of rings (not shown). In a preferred example, the width of the supporting elements 252 is about the same width of an adjacent structural element such as an adjacent crown or strut.
  • the width of the supporting elements 252 is equal to or larger than the width of an adjacent structural element such as an adjacent crown or strut. In yet other examples, the width of the supporting elements 252 is larger than the width of an adjacent structural elements such as an adjacent crown or strut. In yet other example, the width of the supporting elements 252 is smaller than the width of an adjacent structural elements such as an adjacent crown or strut. In some instances, the width along the length of a supporting element or along a structural element such as a strut or a crown may vary. In such examples, the width is the average of the maximum width and minimum width along the length of the supporting element or structural element.
  • Each of the supporting elements 252 has a base end 256 which is attached/connected to the radially expandable circumferential support ring 242.
  • the base end 256 typically has the same width as the rest of the supporting element (as shown) but in other examples, the base may have a larger width than the supporting element width.
  • Each of the supporting elements has a free end 258 which extends into the region between the adjacent struts.
  • the free end 258 has a rounded shape (as shown), or in other examples may have a flat shape (not shown), T shape (not shown) or other shapes or configurations.
  • the supporting elements 252 are shown to be attached to an inner radius or wall of crowns 250 and to be linear, in other examples, the supporting elements may be attached to other locations on the support rings 242 such as attached to struts, and to be linear or non nonlinear.
  • at least some supporting elements are connected to each radially expandable circumferential support ring 242.
  • at least some supporting elements are connected to at least some radially expandable circumferential support ring 242.
  • at least some supporting elements are connected to substantially all radially expandable circumferential support ring 242.
  • each ring comprising a plurality of cells, wherein each cell comprises struts joined by a crown, wherein at least one supporting element is connected to each cell (as shown) on the at least some expandable rings.
  • at least one radially expandable circumferential ring wherein the ring comprising a plurality of cells, wherein each cell comprises struts joined by a crown, wherein at least one supporting element is connected to each cell on the expandable ring (as shown).
  • At least one radially expandable circumferential ring wherein the ring comprising a plurality of cells, wherein each cell comprises struts joined by a crown, wherein at least some supporting elements are connected to at least some cells on the expandable ring (as shown FIG. 8C).
  • at least some radially expandable circumferential support rings wherein each ring comprising a plurality of cells, wherein each cell comprises struts joined by a crown, wherein at least some supporting elements are connected to at least some cells on the at least some expandable rings (as shown).
  • the supporting scaffolds 238 will be laser cut from metal tubes, for example, in the “rolled out” pattern shown in FIG. 8B.
  • the helical coil will have a gap between coils ranging from 0.01 mm to 0.25 mm.
  • at least one membrane 240 extends from the distal end of the distal tip to a proximal region The membrane 240 may be joined, fused, or attached over inner and/or outer surfaces of the expandable scaffold 238.
  • the expandable distal tip 218 and the supporting scaffold 238 are in their non-expanded configurations (or are in the as delivered configuration) which are suitable for introduction through the patient’s vasculature to a target clot location. Once at the target clot location, however, the expandable distal tip 18 and supporting structure 238 will be expanded to engage a clot or a wall of the blood vessel adjacent to clot.
  • the supporting elements 258 in FIGS. 8A to 8C comprise at least one supporting element contained within each cell on one ring, or contained within at least some cells on one ring, form a circumferential envelop about the scaffold circumference along a scaffold length or along the entire length of the scaffold.
  • the circumferential envelop typically has a fixed axial length, width, shape, number of supporting elements per ring, pitch angle, and/or geometry (as shown), and provides support to the one or more expandable membranes to resist collapse of the one or more expandable membranes after expansion from an as delivered configuration to an expanded configuration and a vacuum is applied at a proximal end of the aspiration catheter and the distal tip is blocked or plugged with clot or other substances.
  • the supporting elements are contained within each cell on one ring, or within each ring amplitude, preferably, within the space of struts joined by crowns the same ring, wherein the amplitude comprises the axial distance between two adjacent peaks on the same ring.
  • the supporting elements may have varying lengths, widths, shapes, missing supporting elements (one or more cell within a ring does not have a supporting element), pitch angle, and/or geometry within a ring or along at least some rings, wherein the different widths, lengths, shapes, missing supporting element, or geometries maintains sufficient support to the expandable one or more membrane to prevent collapse of the at least one or more membranes under vacuum in the expanded configuration when the distal tip is blocked or plugged with clot or other substances.
  • the expandable distal tip 18 may be expanded into a variety of different geometries.
  • the expanded geometry will be generally cylindrical 238a, as shown in FIG. 9 A, or may have a conical tip end at the distal end of the generally cylindrical (not shown).
  • the expanded geometry may be generally conical 238b with a base of the cone forming an enlarged distal opening for receiving clot, as shown in FIG. 9B.
  • the expanded geometry may combine expanding and tapering conical sections 238c and 238d, as shown in FIGS. 9C and 9D.
  • the different expansion geometries will be imparted by the shape of the expandable balloon 44, i.e., the supporting scaffold 238 will be malleable and will assume the expanded shape of the expansion balloon.
  • the supporting scaffold 238 will be elastic or superelastic and be pre-shaped by heat treatment or otherwise to a desired expanded geometry when free from constraint, also such as those shown in FIGS. 9 A to 9D.
  • a supporting scaffold 260 pattern includes supporting elements 268 attached to the outer curved walls of crowns 266 which join adjacent struts 264.
  • the supporting elements 268 do not extend between adjacent struts 264 but rather extend into a gap or open space between adjacent radially expanding circumferential support rings 262.
  • the support rings 262 are joined continuously, end-to-end to form a helical pattern.
  • FIG. lOC is an image showing an expandable region of an aspiration catheter with the scaffold pattern of FIGS. 4 A and 4B in a radially constricted configuration (or as delivered configuration) suitable for delivery.
  • FIG. 10D is an image of the same structure shown in FIG. IOC after it has been balloon-expanded to an expanded configuration, preferably to its maximally enlarged configuration suitable for aspiration.
  • the distal end ring is configured to have a flush end with an approximately 90° pitch angle relative to the longitudinal axis in the as patterned or as delivered configuration (as shown).
  • the end and immediately adjacent rings may be configured in various ways.
  • the ring adjacent the end ring is this example was truncated along the circumferential path of the ring and connected to the end ring as shown in FIG. 10 A.
  • the end ring and ring adjacent the end ring may have different acute (or 90°) pitch angles (as shown).
  • the ring before end and end ring may also have same or different cells amplitude, cells periods, structural elements widths, and/or number of crowns.
  • the expandable scaffold 260 pattern has a pitch angle of about 86°.
  • the pitch angle in other examples may range from 70° to 89.9°, preferably may range from 80° to 89° relative to the longitudinal axis in the as patterned or as delivered configuration. It is important to note that even though the supporting elements extend into gap regions (or other spaces) between adjacent rings, usually these supporting elements do not extend into adjacent ring regions, thereby maintaining enhanced deliverability of the expandable scaffold segment into the vascular anatomy.
  • a supporting scaffold 270 having a helical pattern similar to that of scaffold 60 comprises a plurality of radially expandable circumferential support rings 272 including struts 274 and crowns 276.
  • Support elements 278 differ from support elements 68 in that they have bifurcated end support discs. The supporting elements form a circumferential envelop about the scaffold circumference along a scaffold length or along the entire length of the scaffold.
  • the circumferential envelop typically has a fixed axial length, width, shape, and/or geometry (as shown), and provides support to the one or more expandable membranes to resist collapse of the one or more expandable membranes after expansion from an as delivered configuration to an expanded configuration and a vacuum is applied at a proximal end of the aspiration catheter with the distal tip is blocked or plugged with clot or other substances.
  • the supporting elements base is at crowns peaks regions. The supporting elements extend axially beyond each ring amplitude or beyond at least some rings amplitude wherein the amplitude is the axial distance between two adjacent peaks on the same ring.
  • the supporting elements may have varying lengths, widths, shapes, or geometry within a ring or along at least some rings, wherein the different widths, lengths, shapes, or geometries continue to provide support to the expandable one or more membrane to prevent collapse under vacuum in the expanded configuration of the at least one or more membranes.
  • a supporting scaffold 280 has a helical pattern similar to that of scaffolds 260 and 270 comprises a plurality of radially expandable circumferential support rings 282 including struts 284 joined by crowns 286.
  • Support elements 288 differ from support elements 268 and 278 in that they extend primarily in a circumferential direction allowing adjacent support rings 282 to be positioned very closely together in an axial direction prior to expansion. In this example, the supporting elements extend into substantially the entire gap between rings, leaving a small gap in between adjacent ring.
  • This type of supporting elements configuration provides the one or more membranes enhanced resistance to collapse when the membranes are expanded from an as delivered configuration to an expanded configuration and a vacuum is applied at a proximal end of the aspiration catheter.
  • such design configuration where the gap is small is more suitable for anatomy that is not tortuous.
  • one or more supporting elements may be missing within one or more rings providing a non-symmetrical supporting element pattern yet maintaining the resistance to collapse of the expandable membranes.
  • the support elements have generally comprised a straight structure having a base end attached to a radially expandable circumferential support ring and a free end located in a space between adjacent struts, between adjacent struts joined by crowns, or a gap between adjacent support rings.
  • Support element 304a shown in FIG. 13A has a base end attached to an inner radius or wall of crown 302 and a free end terminating in an oval contact pad 305a in a V-shaped, O-shaped space between adjacent struts 300.
  • the oval contact pad 305a has a major axis aligned an axial direction.
  • a support element 304b terminates in an oval contact pad 305b having a major axis aligned in a circumferential direction.
  • Support element 304c in FIG. 13C is similar to the previously described support elements except that it terminates in a triangular contact pad 305c with a pointed tip directed away from the attached crown.
  • Support element 304d in FIG. 13D is similar to all of the previously described support elements except that it terminates in a triangular contact pad 305d with an expanded base directed away from the attached crown.
  • Supporting element 304g shown in FIG. 13G has a base attached to a center of an inside wall of crown 302 and a circular contact pad 305g having a hole in its center circumferentially aligned with the attachment point.
  • Support elements having curved shafts are shown in FIGS. 13E, 13F, 13H, and 131.
  • Support element 304e shown in FIG. 13E has an S-shaped shaft with a base end attached on one side of an outer curve of crown 302 and a circular contact pad 305e circumferentially aligned with the outermost point of the crown.
  • Supporting element 304f shown in FIG. 13F has a base attached to the outermost point on crown 302 and a circular contact pad 305f circumferentially aligned with the outermost point.
  • 13H has a base attached to the outermost point of the crown 302, a shaft with a simple 90° bend, and a circular contact pad 305h axially offset from the outermost point.
  • Supporting elements 304i shown in FIG. 131 have their base ends attached along the length of struts 300 and circular contact pads 305i attached to their free ends.
  • the shaft has an approximately 120° bend.
  • Supporting element 304j shown in FIG. 13J is similar to those shown in FIGS. 8A- 8C having a circular contact pad 305j at the free end of a linear shaft but includes a short split 306j formed in crown 302j to permit an increased radial expansion.
  • supporting elements may have bends, bifurcations, multiple contact pads, and their structural features to enhance their ability to support the expandable membranes in regions between adjacent struts and/or adjacent support rings.
  • supporting element 304k is bifurcated into a Y-shape and has a pair of contact pads 305k.
  • Supporting element 304f shown in FIG. 13L also has a bifurcation with a pair of contact pads 305f and third contact pad 306f located at the point of bifurcation.
  • supporting elements may be formed as linked, linear segments optionally having contact pads at some or all junctions between the links.
  • supporting elements 304m and 304n respectively, each comprise a pair of linear segments with a contact pad 305m and 305n, respectively, at a terminal free end and an inner contact pad 306m and 306n, respectively, at the junction between the segments.
  • the linear segments in supporting element 304m are attached at an approximately 120° angle while the linear segments in supporting element 304n are attached at a right (90°) angle.
  • FIGS. 130 to 13R a variety of T-shaped supporting elements having base ends attached to an inner surface of a U-shaped crown are illustrated.
  • the T-ends may extend into a gap between adjacent rings and may be flush with either ring as shown in FIGS. 130 and 13P. Alternatively, the T-ends may be flush with the ring to which they are attached (FIG. 13Q) or may extend into the intermediate gap without contacting either ring (FIG. 13R).
  • supporting elements within each ring extend in the same direction as shown in FIG. 130. Alternatively, supporting elements within each ring may extend in opposite directions as shown in FIG. 13P.
  • supporting elements having base ends attached to an inner surface of a U-shaped crown may have unattached ends having different terminal geometries extending into a gap between adjacent rings.
  • some of the terminal ends may be provided with a bumper or stop element configured to engage an adjacent ring to maintain a desired gap region therebetween.
  • supporting elements having base ends attached to an inner surface of a Box-shaped, or U-shaped crown may have recessed unattached ends (free ends) which fill essentially all space between adjacent struts on each ring (or which fills or covers substantially all the space between adjacent struts on each ring in the as patterned or as delivered configuration).
  • This is a preferred ring geometry as shown in more detail in FIGS. 11 A to 1 ID discussed in detail below.
  • FIGS. 13U to 13Y and 13P a variety of supporting elements having base ends attached to an outer surface of a U-shaped crown are illustrated.
  • the unattached ends (free ends) of the supporting elements may have T-shaped, L-shaped, deflected, or a variety of other geometries, and will fully or partially extend into a gap between adjacent ring elements, the terminal ends may be flush with an adjacent ring, as shown in FIGS. 130, 13U, 13W, 13X, and 13Y, or may leave an intermediate gap without contacting adjacent ring (FIG. 13V).
  • FIGS. 13Z to 13 AD a variety of supporting elements may be attached to a side of a crown and extend circumferentially toward and adjacent crown.
  • Single lateral supporting elements are shown in FIGS. 13Z, 13 AB, and 13 AC, while a pairs of sliding lateral elements are shown in FIG. 13 AA and 13 AD.
  • the lateral elements may optionally extend over the outer surface of an adjacent crown, as shown in FIG.13 AC.
  • the supporting elements may be formed as “lock and key” structures comprising a straight or male element which is slightingly received in a slotted or “clevis” member.
  • Such supporting elements can accommodate circumferential movement and/or axial movement of adjacent ring elements as the scaffold is radially expanded, such expandable or accommodating supporting elements may extend across and opening of a U-shaped cell (including a pair of struts joined by a crown), as shown in FIGS.
  • the base end of the male element and/or clevis element may be attached to an inner or outer surface of a crown, to an inner surface of a strut, and may extend in a circumferential direction or may be inclined at an angle relative to the circumference. Either or both of the male elements and slash or the clevis element may have one or more bends.
  • FIGS. 13AE to 13AP Various geometries and combinations are shown in FIGS. 13AE to 13AP, but it should be appreciated that many other specific geometries could be utilized.
  • a supporting element may be formed between a pair of adjacent circumferential elements to form a single radially expandable ring, as shown in FIG. 13AQ.
  • Such a “double” ring structure may be formed helically, as separate parallel rings, or in any of the other configurations as shown herein.
  • a particular serpentine ring arrangement comprises U-shaped cells with U-shaped supporting elements extending across the opening between adjacent crowns.
  • the U-shaped supporting elements are configured to expand from a crimped configuration, as shown in FIG. 13AR-1 to an expanded configuration as shown in FIG. 13AR-2 as the ring is radially expanded.
  • FIG. 14 is a “rolled out” view of a further example of a supporting scaffold 410 having adjacently linked radially expandable circumferential supporting rings 412 having differing widths and differently configured supporting elements 414 constructed in accordance with the principles of the present invention.
  • the supporting rings 412 are constructed with pairs of struts 415 joined by crowns 416.
  • Supporting elements 414a are linear beams similar to supporting elements 252 described with reference to FIGS. 8A-8D.
  • Supporting elements 414b have a single bend and are similar to supporting elements 104m shown in FIG. 13M but lacking a middle contact pad between adjacent linear segments and attached to a strut 415 rather than a crown 416.
  • Supporting elements 414c are short, straight beams having a distal contact pad.
  • Supporting elements 414d have a single bend and are similar to supporting elements 104h in FIG. 13H.
  • the scaffold rings as shown can have differing number of crowns on adjacent rings, differing cells periods on adjacent rings, supporting elements having differing shapes, number, and frequency on adjacent rings, differing gaps between rings, and/or differing rings amplitudes.
  • a supporting scaffold 420 comprises a plurality of radially expandable circumferential supporting rings 422 comprising struts 424 and crowns 426. Unlike previous examples, there are no supporting elements attached to the supporting rings 422. Instead, the supporting rings 422 have a pattern which inherently provides enhanced support to an attached expandable membrane when used in an expandable distal tip of an aspiration catheter.
  • the supporting rings comprise serpentine or zig- zag rings having a width W in a range from 0.1 mm to 1 mm, preferably from 0.3 mm to 0.4 mm; a gap G between adjacent rings in a range from 0 mm to 1 mm, preferably from 0.05 mm to 0.4 mm; crowns arranged along axial lines separated by a spacing CS in a range from 0.1 mm to 1 mm, preferably from 0.25 mm to 0.4 mm; and struts diverging from the crowns at an angle a in a range from 0 0 to 90 °, preferably from 20 0 to 40 °, prior to expansion.
  • FIGS. 15C illustrates a further alternative embodiment of the supporting scaffold 440 of the present invention having discrete supporting pads 450 located between struts 444 of a serpentine radially expandable supporting ring 442.
  • the struts 444 are joined by crowns 446 in a conventional manner, and adjacent supporting rings 442 are joined by links 447.
  • the supporting pads 450 are attached to the supporting the membrane 452 in V-shaped regions between adjacent struts 444 but are otherwise not attached to the remaining components of the expandable supporting structure 440.
  • the supporting pads 450 may have a triangular shape corresponding to the V-shaped region in which they are attached. They may also have other shapes such as circular, oval, or other rounded shapes. [0280] As the shown in FIGS.
  • the expandable distal tip 518 and the supporting scaffold 538 of the aspiration catheter 512 are in their non-expanded configurations which are suitable for introduction through the patient’s vasculature to a target clot location. Once at the target clot location, however, the expandable distal tip 518 and supporting structure 538 will be balloon-expanded to engage a clot or a wall of the blood vessel adjacent to clot.
  • the proximal end of the expandable scaffold comprises both expandable segments and non-expandable segments on the proximal end ring and is attached in at least one location to adjacent coil (as shown).
  • the terminal end may be attached to an adjacent expandable ring and/or adjacent non expandable coil in one or more locations by a link and/or attaching pointes on adjacent rings or turns.
  • the proximal end ring of the expandable scaffold may be configured to be substantially non expandable, a segment expandable and a segment that is non expandable on the same ring or is configured to be expandable fully and is separately attached to a structure proximally that is not expandable.
  • a distal end of supporting scaffold 568 includes a terminal ring 560 having an enlarged end 562 (enlarged amplitude) and a tapered end 564.
  • the enlarged end 562 is attached to a distal terminus 566 of a final helical turn of these scaffold 538.
  • the enlarged end 562 is also attached to the tapered end 564 of the terminal ring 560.
  • This “squared” construction eliminates having a free distal end of a ring exposed to the vascular lumen as the aspiration catheter is advanced through the vasculature.
  • FIG. 16E illustrates a preferred embodiment of the scaffold pattern of the present invention where most or all of the supporting structures 552 remain recessed within an axial width of the ring prior to ring expansion and will emerge into the gaps between the adjacent rings only after radial expansion of the distal tip.
  • the axial width is defined by the distance between crowns 550 (as shown by lines 563) where the distal tip 558 of each tab-like supporting structure remains between adjacent struts 548 until distal tip expansion, [0283] While it is preferred that the supporting elements 552 remain recessed, as shown in FIG. 16E, the distal tips 559 of the cantilevered supporting elements of the present invention may also protrude into the gap regions outside of lines 563 prior to radial expansion, as shown in FIG. 16F, although such construction will generally be less flexible than otherwise similar recessed constructions.
  • exemplary helical supporting structures have usually consisted of a single, helically wound serpentine, zigzag or other ribbon having bends that allow for elongation upon radial expansion of the associated ring.
  • supporting structures 700 and 702 may have two, three, four, or more helically nested helical rings.
  • the supporting structure 700 includes first and second helically nested rings 710 and 712, respectively.
  • the supporting structure 702 includes first, second, and third helically nested rings 720, 722, and 724, respectively.
  • FIGS. 17A and 17B illustrate how the “pitch angle” of a helical scaffold can be measured.
  • FIG. 17A illustrates a “rolled-out” pattern of an exemplary helical scaffold 600 in its crimped or pre-expanded configuration
  • FIG. 17B illustrates a “rolled-out” pattern of the same helical scaffold 600’ in its radially expanded configuration.
  • the pitch angle of the pre-expanded scaffold 600 is measured between a line LI along the longitudinal axis of the scaffold and a line L2 drawn parallel to the rings 602 in the scaffold.
  • the pitch angle di of the scaffold 600 in the pre-expanded or in the as delivered configuration is typically from 70° to 89.9° or more typically from 80° to 89.9, preferably from 84° to 89.9°, and more preferably from 85° to 89° degrees, and most preferably from 86° to 88°.
  • the pitch angle d2 will greater than the pitch angle di for any given scaffold since the pitch angle increases as the scaffold radially expands, approaching 90° as the scaffold fully expands.
  • FIGS. 17C-17E illustrate distal tip supporting scaffolds having varying pitch angles.
  • Supporting scaffold 606 shown in its pre-expanded configuration has a pitch angle of 87°.
  • Supporting scaffold 608 shown in its pre-expanded configuration has a pitch angle of 86.
  • Supporting scaffold 609 shown in its pre-expanded configuration has a pitch angle of 85°.
  • FIGS. 18A-18C are detailed views illustrating different bending patterns that can be utilized in the radially expandable distal tip rings of the present invention.
  • Supporting rings 620 having serpentine bending patterns are shown in FIG. 18 A.
  • Supporting rings 622 having zigzag bending patterns are shown in FIG. 18B.
  • Supporting rings 624 having box box-shaped (square-shaped) bending patterns are shown in FIG. 18C.
  • FIGS. 6and 18E are side and perspective views of a scaffold 630 having helically arranged radially expandable rings 632 with a repeating omega-shaped cell pattern.
  • FIG. 19 illustrates the how a faceted outer surface of the radially expandable distal tip region of the aspiration catheter of the present invention approaches a circular perimeter (achieves enhanced “circularity”).
  • Cross-sectional views of an exemplary radially expandable distal tip region 640 are shown in a pre-expanded configuration (640) and a radially expanded configuration (640’).
  • a circumferentially expanding ring 642 is embedded in a polymer membrane 644, so that the outer surface of the radially expandable distal tip region forms a number of relatively flat facets 646 between struts 648 of the scaffold 642.
  • the radially expandable distal tip region has a first radius f2 from an axial center line C of the ring to the circumferential center of each facet 646 and a second radius R2 from the axial center line C of the ring to the a circumferential edge of each facet 646, and wherein the length of the first radius f2 is from 80% to 99.9% of the length of the second radius R2, preferably being from 95% to 99.5%, more preferably being from 97.5% to 98.5%, and most preferably being from 98.5% to 99.5.
  • the radially expandable distal tip region In its expanded configuration 640’ (e.g. a radial expansion of 50% or less, usually of 100% or less, and sometimes of 200% or less), the radially expandable distal tip region has a first radius Ri from the axial center line C of the ring to the circumferential center of each strut 648 and a second radius n from the axial center line C of the ring to a circumferential edge of each facet 646, and wherein the length of the first radius is from 75% to 99% of the length of the second radius, preferably being from 97% to 99%, often being from 98% to 99%, more typically being 98.5%.
  • a circularity in the expanded configuration greater than 97% is preferred, greater than 98% is more preferred, and greater than 98.5% is most preferred,
  • FIG. 20 identifies various characteristics that can be used to configure the structure of a helical radially expandable distal tip rings of the present invention, with values as shown in Table 1 below. TABLE 1 : Characteristics of a Helical Ring Pattern
  • FIGS. 21 A to 21C are side, perspective, and “rolled-out” views of an expandable scaffold 660 comprising a plurality of transversely oriented, axially linked expandable rings 662 joined by axial links 664.
  • FIG. 22 identifies various characteristics that can be used to configure the structure of an expandable scaffold comprising a plurality of transversely oriented, axially linked expandable rings, such as that shown in FIGS. 21A-21C, with values as shown in Table 2 below.
  • FIGS. 23A and 23B are side and “rolled-out” views of an expandable scaffold 380 comprising a plurality of parallel, axially linked expandable rings 682 which are joined by axially links 684 inclined relative to a longitudinal axis of the scaffold at an acute pitch angle a 3 .
  • FIG. 24 is a “rolled-out” view of an expandable scaffold 690 having segments 692 and 694 with cells aligned in-phase and out-of-phase, respectively.
  • FIG. 25 is a “rolled-out” view of an expandable scaffold 800 comprising a plurality of rings 802 with gaps 804 therebetween having varying lengths.
  • FIG. 26A is a “rolled-out” view of an expandable scaffold 900 comprising a plurality of rings 902 with gaps 904 therebetween arranged in a helical pattern.
  • the rings 902 are “smooth,” i.e., linear, and free from bends and curves in the rolled-out pattern.
  • the rings 902 will each have a serpentine pattern.
  • a simple serpentine pattern comprising struts 906 joined by crowns 908 is illustrated in FIG. 26B, the rings 902 may comprise any cell patterns described herein or otherwise known in the art.
  • FIGS. 26C to 26E are rotated side views of the expandable scaffold 900 of FIG. 26A.
  • the view of scaffold 900 as shown in FIG. 26D is rotated 90° in a first rotational direction relative to the view in FIG. 26C while view shown in FIG. 26E is rotated 90° in the opposite rotational direction.
  • the rings 902 of scaffold 900 are “smooth,” i.e., free from bends, the side view does not vary as the scaffold is rotated about its longitudinal axis.
  • FIG. 27A is a “rolled-out” view of an expandable scaffold 920 comprising a plurality of rings 922 with gaps 924 therebetween arranged in a helical pattern where individual rings have a first curved shape in the rolled-out pattern.
  • the individual rings 922 are non-linear, including two curved or bent regions 532, one of which spans the joined ends, e.g., 534a and 534b when the scaffold is rolled.
  • the rings 922 will each a serpentine pattern.
  • a simple serpentine pattern comprising struts 926 joined by crowns 928 is illustrated in FIG. 24B, the rings 922 may comprise any cell patterns described herein or otherwise known in the art.
  • FIGS. 27C to 27E are rotated side views of the expandable scaffold 920 of FIG. 24A.
  • the view of scaffold 920 as shown in FIG. 27D is rotated 90° in a first rotational direction relative to the view in FIG. 24C while view shown in FIG. 27E is rotated 90° in the opposite rotational direction.
  • the curves 532 in rings 922 of scaffold 920 cause the observed inclination of each ring 922 to shift from a rightward tilt, as shown in FIG. 27D, to a leftward tilt, as shown in FIG. 27E.
  • FIG. 28A is a “rolled-out” view of an expandable scaffold 940 comprising a plurality of rings 942 with gaps 944 therebetween arranged in a helical pattern where individual rings have a second curved shape in the rolled-out pattern.
  • the individual rings 942 are non-linear, including three curved or bent regions 952 (one of which spans the joined ends 954a and 554b when the scaffold is rolled).
  • the rings 942 will each have a serpentine pattern.
  • a simple serpentine pattern comprising struts 946 joined by crowns 948 is illustrated in FIG. 28B, the rings 942 may comprise any cell patterns described herein or otherwise known in the art.
  • FIGS. 28C to 28E are rotated side views of the expandable scaffold 940 of FIG. 28A.
  • the view of scaffold 940 as shown in FIG. 28D is rotated 90° in a first rotational direction relative to the view in FIG. 28C while view shown in FIG. 28E is rotated 90° in the opposite rotational direction.
  • the curves 552 in rings 942 of scaffold 940 cause the observed inclination of each ring 942 to shift back-and-forth as the scaffold is rotated relative to its longitudinal axis, as can be seen by comparing the imaged in FIGS. 28C, 28D, and 28E.
  • FIG. 29 is “rolled-out” view of a ring pattern comprising rings 980 having S-shaped expandable elements 982 joined by non-extendable circumferential links 984 shown prior to expansion.
  • FIG. 30 is “rolled-out” view of a ring pattern comprising rings 990 formed from a wire bent into a serpentine pattern having integrated cantilevered supporting elements 992 formed by tight U-shaped turns that are glued, soldered, welded, or otherwise bonded together to prevent separation.
  • FIGS. 31A and 3 IB are “rolled-out” views of a ring pattern comprising closed-cell box rings 1000 shown in its non-expanded and expanded configurations, respectively. Boxes 1002 in each ring circumferentially elongate from a rectangular, non-expanded shape as shown in FIG. 31 A to a generally hexagonal, elongated shape, as shown in FIG. 3 IB. Such elongation allows each ring to radially expand in response to an opening force provided by a balloon or other deployment tool.
  • FIGS. 32A and 32B are “rolled-out” views of a rings 1010 comprising closed-cell boxes 1012, shown in its non-expanded and expanded configurations, respectively.
  • the rings 1010 are similar to the rings 1000 illustrated in FIGS. 31 A and 3 IB except that they further comprise cantilevered supporting elements 1014 recessed between attached to circumferential links 1016 circumferentially adjacent box elements 1012 in the non-expanded configuration (FIG. 32A).
  • the cantilevered supporting elements 1014 remain in spaces between adjacent expanded boxes to provide further support for the surrounding membrane (not shown) after the rings are radially expanded, as shown in FIG. 32B.
  • FIGS. 33A and 33B are “rolled-out” views of rings 1020 comprising alternative closed-cell boxes formed from side members 1022 and cross members 1024.
  • the side members are initially formed in a U-shape when the rings are in a non-expanded configuration, as shown in FIG. 33A.
  • the U-shape elongates as the rings are radially expanded, as shown in FIG. 33B.
  • FIGS. 34A to 34C illustrate an exemplary method for embedding a radially expandable supporting scaffold 1030 in a polymer membrane 640 (one or more membranes formed from the same or different material).
  • the supporting scaffold 1030 has a serpentine pattern with struts 1032 having gaps 1034 therebetween, as shown in FIG. 31 A.
  • the supporting scaffold 1030 may be embedded in the polymer membrane 640 by first placing sheets 1036 and 1038 of the desired polymer or polymers over exterior and interior surfaces of the rings 1030, as shown in FIG. 3 IB. By applying heated and pressure to the polymer sheets, the polymer will flow into the gaps 1034, forming a continuous polymer membrane matrix 640 having exterior and interior surfaces 642 and 644, respectively, as shown in FIG. 31C.
  • a distal tip comprising scaffold 1030 and the polymer membrane matrix 640 is shown in its radially expanded configuration in FIG. 32.
  • the polymer matrix 640 is elastic, allowing it to stretch and thin as the distal tip is expanded. While the polymer membrane will usually exert a radially closing force, the expanded supporting scaffold 1030 will have sufficient hoop strength (crush resistance) to hold the distal tip open against both the elastic force of the polymer membrane and the vacuum applied during clot aspiration.

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Abstract

Un cathéter d'aspiration présente une région distale extensible comprenant un échafaudage à membrane expansible conçu pour s'étendre radialement afin d'améliorer l'aspiration lorsqu'une pression négative est appliquée à une extrémité proximale du cathéter. La région distale extensible peut être formée en continu avec un corps de cathéter ayant un orifice de fil-guide formé dans une paroi latérale. En variante, la région distale extensible peut être portée au niveau d'une extrémité distale d'une tige de positionnement pour permettre le positionnement et l'expansion à l'intérieur d'un corps de cathéter formé séparément.
PCT/US2024/032751 2023-06-08 2024-06-06 Systèmes de cathéter d'aspiration Ceased WO2024254268A2 (fr)

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US202363506886P 2023-06-08 2023-06-08
US63/506,886 2023-06-08
US202363586309P 2023-09-28 2023-09-28
US63/586,309 2023-09-28
US18/482,711 2023-10-06
US18/482,711 US12076504B2 (en) 2022-03-28 2023-10-06 Aspiration catheters with expandable distal tip

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CN121796004A (zh) * 2026-03-11 2026-04-07 湖南省华芯医疗器械有限公司 一种鞘管、导引鞘和内镜组件

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US7686825B2 (en) * 2004-03-25 2010-03-30 Hauser David L Vascular filter device
EP3967266B1 (fr) * 2012-11-15 2023-07-12 Nfinium Vascular Technologies, LLC Échafaudage vasculaire temporaire et dispositif de striage
US9433429B2 (en) * 2013-03-14 2016-09-06 Neuravi Limited Clot retrieval devices
US20220296261A1 (en) * 2017-05-04 2022-09-22 Anoxia Medical Inc. Catheter Assembly for Blood Clots Removal
CA3089554A1 (fr) * 2018-01-25 2019-08-01 Ischemicure Ltd. Dispositifs, systemes et procedes pour retirer des caillots sanguins

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN121796004A (zh) * 2026-03-11 2026-04-07 湖南省华芯医疗器械有限公司 一种鞘管、导引鞘和内镜组件

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