Cardiac valvular bioprosthesis and the proceeding of achievement
1. TECHNlCAL FIELD
She present invention relates to a cardiac valvular bioprosthe- tics,used in cardiac valvular replacements and to the proceeding of achievement.
2. BACKGROUND OF PRIOR ART
Mettallic valvular prosthetic of different constructions are known.
The drawback of these prosthesis that the beares are obligatory submited to a chronical anticoagulant treatment.
The bioprosthetics made from a pericardium of calf,human dura mater and broad fascia are more known.
The drawback of these prosthesis is;their cuspa does not. present an adequate anatomical form and their resistence is reduced.
The valvular bioprosthetics from an aorta of domestic pig are also known.The drawback of these bioprosthetics is that,due to the short fibres with great fibrilar spaces for the fat storehouse, they present a more reduced resistence in time.
3. BRIEF SUMMARY OF INVENTION
The cardiac valvular bioprosthetics, in accordance with the invention,remove the above drawback,in a view to obtain a great resistence by using as biological material, an aortic valva from wild boar, bear or other animal,with a special structure of the
tissues,applied on a metallic support or plastic material by agency of a relation stratum from knited textile material and the heart fixation making by agency of a burclat ring.
The biologic material contains: an aortic valva of wild boar,bear or other animal,taked with the aortic wall and interventricular septum,immediately after the animal sacrifice.
The aortic valva of wild boar is a valva with three depth cuspae which achieve some nests which much proIabe under the horizontal plan which passes through the valvular ring.To transligh the cuspae appear semitransparent,the maximum tranparence being to the center cuspae.Also,the presence of dense fascicolae of fibres is observed in length of cuspa,between ccmisures,.approximately parallel with the cuspa edge which is free,the length of these fibres and the parallel sitting(small spaces between the fibres) giving to the tissue an incresed resistence and elasticity,tissue submited to a very intensive mechanic requirement.
The support for the valva is made from a basis and a superstructure.The basis has a circular form with the diameter depending the valva diameter which must be replaced(between.1-2mm),interrupted by resistence pillars from which someones,disposed in the middle of flankeies basis and.the others,in the middle of curve between two flankeies.
The superstructure is formed from three flankeies like an isosoel triangle,disposed at 120 ,between the superior tips.
The passing from a tip to the other,is formed on a curve which fidelly follows the natural form of biologic valva which must be mounted on the support.
Each triangle flankeies is disposed with the small side on the support basis, the opposite tip to basis is rounded and,in interior has a window of the same form and a prominence for fixing the seam.
The burelat ring can be made from knited textile material,plastic material or siliconal material. The proceeding of achievement of cardiac valvular bioprosthetic consists in taking the biologic material from the wild boar,immediately after sacrifice.They take the aortic valva with the aortic wall
and a side of the interventricular septum,it is washed in physio- logic serum in a view to eliminate the blood,the muscular fibres are eliminated from the septal cuspa and,from the aorta,the surplus of tissue.Swabs are introduced in cuspae for maintaining the form and they are introduced in keeping solutions and sterilization, they are stored in containers at 6-12° and after 48h,the biologic material is pulled and prepared for mounting on tho metallic suppor
The preparing consists in eliminating all muscular fibres from the cuspae surface and cutting the aortic wall in concordance with the form of superior edge of metallic support,dressed with a textile stratum.
The metallic support is separately prepared by dressing with knited textile material with a tubular form, introduced from down- wards to upwards through the metallic support and after,the superior edge of the tube(textile material) is bended over the flankeies tips and is pulled under the inferior edge of support with 8-10mm shorter than the other edge of inferior textile tube. Further on,the surplus of textile material is remove,comprised between flankeies and the edge must be cut with thread from the exterior to the interior of edges for being plugged.
The exterior cylinder is fixed in few points(six) of the basis of metallic support,the surplus is cut and bended over its edge, the burelat ring is applied and fixed in few points on the support basic(through the textile stratum and the tube of support basis) . The edge of the interior cylinder must be bended over the burelet ring and cut around with a permanent thread. Further on, the biologic material,previously prepared on the dressed support is mounted by cutting with two threads and its introduction being made through the support interior.! seam is made between the aortic valvular ring and the inferior edge of the dressed metallic support, the second seam is made between the prepare aortic wall and the superior edge of the support.After ail these, a band from the same knited textile material is applied on the superior edge of dressed support and the biologic material thus sewed so that it covers the seam between the biologic material and
support for protecting the seam.
Until its using, all make procedeeing is kept in keeping solution and sterilization , accomplishing a sterile medium.
4.MEANS OF INDUSTRlAL ACHIEVEMENT
The cardiac valvular bioprosthetics, in accordance with the invention, can be achieved on an industrial or semiindustrial way providing,first at all, the source of biologic material as well as the means necessary for its make.For obtaining the prosthesis replacements in man,it is necessary to make their tests by some apparatus which determine their resistence and their hidrodynamic performances..
5.SHORT PRESENTAION OF THΕ FIGURSS
We illustrate an achievement also regarding the figures 1-4 representing:
-fig.1-sight with section through bioprosthetics -fig.2-sight with section through the flankey tip A-A -fig.3-sight with section B-3
-fig.4-sight from face of metallic support
6.DETAILED DESCRIPTION OF INVENTION
The cardiac valvular bioprosthetics,in accordance with the invention,is made from a biologic material 1(aortic valva of wild boar,bear or other animal) with a special structure which is applied on metallic support 2 or plastic material by agency of a stratum 3 for contact from knited textile material and the fixation on the heart accomplishing by agency of a burelat ring 4 from textile material,plastic material or siliccnic rubber.
The aortic valva of wild boar is a prosthesis with three deep cuspae a,formed from dense fascicolae of fibres on the cuspa length between comisures approximately parallel with the free edge of it.
The support 2 for the prosthesis 1 is made from a basis A and superstructure B.
The basis A has a circular form with a diameter depending of prosthesis diameter which must be replaced(betv/een 15-33mm)and on the circumference,it presents a tube b,1-2mm,interrupted by some resictence pills c from which someones in the middle of the flankeies d and the others in the middle of the curve between two flankeies.
The superstructure B is formed by three flankeies d with an isoscel triangle form, disposed at 120° between the superior tips The passing from a tip to the other is made on a curve f which fidelly follows the natural form of the biologic prosthesis which must be mounted on the support.
Each flankey d is set with the small side g on the basis A, the tip opposite to the basis,is rounded and,in interior ,presents a window h of the same form and a prominence i for fixing the seam material.
The proceeding of achievement of cardiac valvular bioprosthetics consists in taking the aortic prosthesis l with the aortic wall j and a side from interventricular septum k of the wild boar, they wash it in physiologic serum for blood removing,the muscular fibres of septal cuspae are eliminated and, also,the tissue suprplus of the aorta.The swabs are introduced in cuspae for the form maintaining and they are introduced in keeping solutions and sterilization with glutaraldehida 0,625,tamponed with phosphat at Ph 7,27,4.They are deposited in containers at 5-12° G,after 48h,the biologic material is taken and prepared for its mounting on the support 2 .
The preparing consists in eliminating the muscular fibres of the cuspae surface a and in cutting the aortic wall j in accordance with the superior edge of the dressed support 2 with the stratum 3 from textile material.The metallic support 2 is separately prepared by dressing with knited textile material 3 of tubular form,introduced from downwards to upwards through the support 2.
The material 3 is bended over the tips e and the tube 1 pull under the inferior edge of a support 2 with 8-10mm shorter than the end m of a material 3.Further on,the material surplus comprise between the flankeies d and the edges are cut with thred from the exterior to the interior of the edges for being plugged.
The cylinder 1 is fixed in few points(six) on the basis A,the surplus is cut and it is bended over the edge,the burelat ring 4 is applied and fixed in few points on the basis A.The cylinder edge m is bended over the ring 4 and they cut around with a permanent thread.
Further on,the biologic material 1 is mounted and previously prepared on the support 2 by sewing with two threads,its introduction being made through the interior of the support 2.
A seam is made between the aortic valvular ring and thevinferior edge of the support 2 and the second seam,between the prepared aorti wall j and the superior edge of the support 2.After all these,a band 5 from the same knited textile material is applied on the super or edge of the dressed support 2 and the biologic material j so cut that it covers the seam from the biologic material j and the support 2 for its protection.
All proceeding of achievemnt is made in sterile medium.
Until its utilisation,tho prosthesis must be kept in keeping solution and sterilisation.
7. ADVANTAGES
The cardiac valvular prosthesis and the proceeding of its achievement present the following advantages;
-a greater resistsnee in time
-no requires a permanent anticoagulant treatment
-the employment of this prosthesis is indicated specially for certain categories of patients as: young women,ulcer,with disorders of sanguine chrasa, special social circumstances (braάipsychics, difficult access to medical assistence) ,hypertensive patients(to whom the prosthesis of pig are unadvisable).