TWI511702B - Methods for the measurement of endothelial cell dilatation - Google Patents

Description

Method for measuring endothelial cell expansion function

The present invention relates to a measuring method, and more particularly to a method for measuring the function of endothelial cell expansion.

The expansion function of endothelial cells (Endothelium) on the inner wall of arterial vessels affects the degree of expansion of arterial blood vessels. Therefore, some studies on the expansion function of endothelial cells have been proposed and used as a basis for assessing the elasticity of vascular arteries, and then by arterial vessels. The degree of elasticity is used to infer the possibility of developing cardiovascular disease and as an indicator for preventing the disease.

In the paper 'John E. Deanfield, Julian P. Halcox and Ton J. Rabelink, "Endothelial Function and Dysfunction: Testing and Clinical Relevance," Circulation, 115: 1285-1295, 2007. 'Proposed a method for measuring blood vessels by ultrasonic technology The method of Endothelial Flow-mediated Dilatation (FMD), which has the following disadvantages:

(1) The internal diameter of the blood vessel must be measured by relying on a high-frequency ultrasonic instrument with an expensive equipment.

(2) The instrument must be operated correctly by a skilled doctor or technician.

(3) The measurement must be carried out in a professional medical institution and cannot be used universally.

(4) Due to the use of high-frequency ultrasound to measure the endothelial cell expansion function index of the artery, it is limited by the accuracy of measuring the blood vessel diameter. Greatly reduce the accuracy and reliability of the endothelial cell expansion function index.

(5) The amount of change in the diameter of the blood vessels caused by the vascular occlusion before and after the vascular occlusion is small, resulting in the endothelial cell expansion function index measured by high-frequency ultrasound, and its sensitivity is not high enough.

Accordingly, it is an object of the present invention to provide a method for measuring endothelial cell expansion function which avoids the above-mentioned deficiency, reduces equipment cost, and improves sensitivity.

A method for measuring the function of endothelial cell expansion, which measures the expansion function of vascular endothelial cells by applying pressure to one of the limbs of a subject, and includes the following steps: setting the internal gas pressure of the balloon to a low pressure pre-pre Setting a value to apply pressure to one of the limbs of the subject; measuring the air pressure in the airbag to obtain a change in the internal pressure of the balloon during a normal period of the blood vessel; setting the internal gas pressure of the airbag to a high pressure preset a value for applying pressure to one of the limbs of the subject; and then depressing the balloon to the preset value of the low pressure, measuring the air pressure in the balloon to obtain a change in the intravesical pressure of the vascular reactive hyperemia period Comparing the amount of change in the intravesical pressure of the vascular reactive hyperemia period with the amount of change in the intravesical pressure of the normal period of the blood vessel to obtain a difference value; and dividing the difference value by the amount of change in the internal pressure of the balloon during the normal period of the blood vessel An index value for the expansion function of a vascular endothelial cell is obtained.

Another object of the present invention is to provide an endothelial cell expansion functional cell expansion measuring device which avoids the above-mentioned deficiency, and which reduces equipment cost and sensitivity.

A measuring device for endothelial cell expansion function, which is suitable for measuring the expansion function of vascular endothelial cells of one of the limbs of a subject, and comprising: an air bag covering one of the limbs of the subject and used for the test Applying pressure to one of the limbs; a gas pressure adjusting circuit coupled to the air bag and controlled to change the internal gas pressure of the air bag; a pneumatic sensing circuit coupled to the air bag for measuring the air pressure in the air bag And a processor electrically connected to the air pressure adjusting circuit and the air pressure sensing circuit, and controlling the air pressure adjusting circuit to set the internal gas pressure of the airbag to a low pressure preset value, to one of the limbs of the subject Applying pressure, and receiving the air pressure sensing circuit to measure the airbag internal pressure change amount of a normal period of the blood vessel obtained by measuring the airbag; and the processor further controls the air pressure adjusting circuit to set the internal gas pressure of the airbag to one The high pressure preset value is used to apply pressure to one of the limbs of the subject, and then control the air pressure adjusting circuit to release the airbag to the low voltage preset value, and receive the air pressure sensing circuit to measure the The amount of change in the intravesical pressure of a vascular reactive hyperemia period obtained during the pressure in the capsule; and the processor compares the amount of change in the intravesical pressure of the vascular reactive hyperemia period with the change in the internal pressure of the balloon during the normal period of the vascular To obtain a difference value; the processor further divides the difference value by the change in the intravesical pressure of the vascular normal period to obtain an index value of the vascular endothelial cell expansion function.

The above and other technical contents, features and advantages of the present invention will be apparent from the following detailed description of the preferred embodiments.

As shown in FIG. 1, a preferred embodiment of the endothelial cell expansion function measuring device of the present invention is coated with an airbag bag or a pulse pressure bag to cover the upper half of one of the subject's limbs (both hands or feet). Or the lower half, and inflating and pressing the airbag bag or the pulse pressure bag to apply pressure to the covered limb part, thereby measuring the function of endothelial cell expansion for evaluation of early arteriosclerosis, and includes: The air bag 5, a gas pressure adjusting circuit 6, a processor 7, a gas pressure sensing circuit 8, and a screen 9.

The airbag 5 covers the upper arm of the subject and is connected to the air pressure adjusting circuit 6 and the air pressure sensing circuit 8.

The processor 7 is electrically connected between the air pressure adjusting circuit 6, the air pressure sensing circuit 8, and the screen 9.

The air pressure adjusting circuit 6 includes a digital analog converter 61, a pump controller 62, and a pump 63.

The digital analog converter 61 is electrically connected between the processor 7 and the pump controller 62, and the pump 63 is electrically connected between the pump controller 62 and the airbag 5.

The air pressure sensing circuit 8 includes a sensor 81, a band pass filter 82, an amplifier 83, and an analog digital converter 84.

The sensor 81 is connected between the air bag 5 and the band pass filter 82, and the amplifier 83 is connected between the analog bit converter 84 and the band pass filter 82. The analog bit converter 84 is electrically connected to the amplifier 83 and processed. Between the 7th.

Referring to Figures 1 and 2, the endothelial cell expansion function measuring device performs a measurement method of endothelial cell expansion function, and the endothelial cell expansion function measurement method comprises the following steps:

Step 1: The processor 7 controls the air pressure adjusting circuit 6 to set the internal gas pressure of the airbag 5 to a low pressure preset value to apply pressure to the upper arm of the subject, and then measure by the air pressure sensing circuit 8. The air pressure in the air bag 5 is used to obtain a change in the internal pressure of the airbag in a normal period of the blood vessel.

Among them, the physical meaning of the change of the internal pressure of the balloon during the normal period of the blood vessel is as follows: because the blood pressure increase and decrease of the upper arm of the subject will increase or decrease the volume of the blood vessel, thereby causing the volume of the airbag 5 to be inversely changed, and the volume of the airbag 5 is changed. Moreover, the internal gas pressure of the airbag 5 is changed up and down by the preset value of the low pressure, and the value of the up and down change is the amount of change of the internal pressure of the airbag in the normal state of the blood vessel. In the embodiment, the low pressure preset The optimum range of values is 30 to 60 mm Hg.

Referring to Figures 1 and 3, step 1 includes the following sub-steps:

Step 11: The processor 7 sends a digital control signal for enabling to the air pressure adjusting circuit 6.

Step 12: The air pressure adjusting circuit 6 receives the digital control signal for enabling, and increases the internal gas pressure of the airbag 5 by 0 according to the digital control signal.

The detailed method of increasing the pressure from 0 in step 12 is: the digital analog converter 61 converts the received digital control signal into an analog control signal having an enabled voltage level, and supplies it to the pump controller 62. The purge controller 62 sends a pressurization signal to cause the pump 63 to provide a pressurized mechanical force that causes the internal gas pressure of the bladder 5 to increase by zero.

Step 13: The air pressure sensing circuit 8 measures the air pressure in the airbag 5 to obtain a digital measurement signal of a specific period air pressure value.

The detailed measurement of the air pressure in the airbag 5 in step 13 is: the sensor 81 converts the measured air pressure value into a voltage signal, and the voltage signal is first filtered by the band pass filter 82. The noise is amplified by the amplifier 83 to obtain an analog measurement signal, and the amplitude value of the analog measurement signal in the specific period is converted to the same by the analog-to-digital converter 84. The digital measurement signal of the specific period air pressure value, wherein, in the embodiment, the optimal range of the specific period is 1 to 3 cardiac periods, and the optimal bandwidth of the band pass filter 82 is 0.01 Hz to 30 Hz. between.

Step 14: The processor 7 receives the digital measurement signal of the specific period air pressure value, and estimates an average air pressure value according to the specific period air pressure value, and compares whether the average air pressure value reaches the low pressure preset value, and if not Then, return to step 11, and if yes, proceed to step 15.

Step 15: The processor 7 sends a digital control signal for pause to the air pressure adjusting circuit 6, and according to the difference value between the maximum value and the minimum value of each of the cardiac cycles, the internal pressure of the blood vessel is normal. The amount of change.

The detailed method of step 15 is: the processor 7 finds the relative high value and the extremely low value of the air pressure value in each cardiac cycle during a normal state of the blood vessel to calculate the relative value of the air pressure value in each cardiac cycle. The extremely high value and the extremely low value are used to obtain the difference value of the internal pressure of the balloon in each cardiac cycle, and the difference value of the intracardial pressure of the most stable and continuous plurality of intracardial pressures in the intracardial pressure difference value of each cardiac cycle is further found, and the The average value of the intracardial pressure difference of the majority of the cardiac cycle is used as the change of the intravesical pressure of the normal period of the blood vessel, wherein the optimal range of the normal period of the blood vessel is 3 to 30 seconds, and it is worth noting that the stable and continuous The difference in the internal pressure of the balloon during the majority of the cardiac cycle refers to the relatively stable and continuous 3 to 15 cardiac cycle internal pressure difference values during the normal state of the blood vessel.

Step 16: The air pressure adjusting circuit 6 receives the digital control signal for suspension and no longer pressurizes the airbag based on the digital control signal.

The detailed method of no longer pressurizing the airbag in step 16 is: the digital analog converter 61 converts the received digital control signal for pause into an analog control signal having a pause voltage level to be supplied to the pump. The controller 62 causes the pump controller 62 to stop issuing the pressurizing signal so that the pump 63 does not provide a pressurized mechanical force to avoid affecting the internal gas pressure of the air bag 5.

Referring to FIG. 1 and FIG. 2, step 2: the processor 7 controls the air pressure adjusting circuit 6 to set the internal gas pressure of the airbag 5 to a high pressure preset value to apply pressure on the upper arm of the subject, so that the The blood of the upper arm of the subject is unable to circulate during a high pressure blocking period, and then the pressure is released to a low pressure preset value, and the air pressure in the airbag 5 is measured by the air pressure sensing circuit 8 at a reactive hyperemia time to obtain a blood pressure. The amount of change in intravesical pressure during vascular reactive hyperemia.

In this embodiment, the optimal range of the high-pressure blocking time is 3 to 5 minutes, and the optimal range of the high-pressure preset value is 150 to 200 mmHg, and the optimal range of the reaction congestion time is 3~ 15 minutes.

Referring to FIG. 1 and FIG. 4, the step 2 includes a plurality of sub-steps 21~26. The sub-steps 21 and 23 are the same as steps 11 and 13, and the difference between step 22 and step 12 is increased from the low-voltage preset value. Press, and sub-steps 24~26 are as follows:

Step 24: The processor 7 receives the digital measurement signal of the specific period air pressure value, and estimates an average air pressure value according to the specific period air pressure value, and compares whether the average air pressure value reaches the high pressure preset value, and if not Then, return to step 21, and if yes, proceed to step 25.

Step 25: The processor 7 sends a digital control signal for the pause to the air pressure adjustment circuit 6.

Step 26: The air pressure adjusting circuit 6 receives the digital control signal for the pause and no longer pressurizes the airbag 5 based on the digital control signal for the pause.

Step 27: After the high voltage blocking time, the processor 7 sends a digital control signal for releasing the pressure to the air pressure adjusting circuit 6.

Step 28: The air pressure adjusting circuit 6 receives the digital control signal for pressure relief, and depressurizes the airbag 5 from the high voltage preset value to the low voltage preset value according to the digital control signal for pressure relief.

The detailed method of releasing the airbag 5 in step 28 is as follows: the digital analog converter 61 converts the received digital control signal for pressure relief into an analog control signal having a pressure relief level and provides the pump with an analog control signal. The controller 62 causes the pump controller 62 to emit the pressure relief signal to cause the pump 63 to provide a pressure relief mechanical force, which causes the internal gas pressure of the airbag 5 to be decremented from the high pressure preset value until the air pressure When the average value of the measurement signal or the like reaches the low voltage preset value, the processor 7 issues a digital control signal for the pause to cause the adjustment air pressure circuit 6 to stop releasing the pressure on the air bag 5.

Step 29: After the high pressure blocking time, the air pressure sensing circuit 8 measures the air pressure in the airbag to obtain a digital measurement signal having a blood pressure value of the vascular reactive hyperemia period (because similar to step 13, it is not repeated here) And calculating the difference between the maximum value and the minimum value of the blood pressure value in the vascular reactive hyperemia period, and the average value of the difference between the internal pressure of the relatively large and continuous 3 to 15 cardiac cycles in the vascular reactive hyperemia period The amount of change in the intra-balloon pressure ΔP _{C of the} vascular reactive hyperemia period is similar to the step 15 in that the amount of change in the intra-balloon pressure of the vascular reactive hyperemia period is similar, and therefore will not be described here.

After the end of the vascular reactive hyperemia period, the air pressure adjusting circuit is controlled by the processor to depressurize the airbag and compare whether the average air pressure value reaches about 0 mmHg. If yes, stop the pressure release, otherwise continue to relieve pressure. Until the average pressure value reaches about 0 mmHg.

Referring to FIG. 1 and FIG. 2, step 3: processor 7 compares the change of the intra-balloon pressure ΔP _{C of} the vascular reactive hyperemia period with the change of the intra-vessel pressure of the vascular normal period ΔP _{C, 0} to obtain a difference. Value (ΔP _C - ΔP _{C, 0} ).

Step 4: The processor 7 difference value _{(△ P C - △ P C} , 0) divided by the balloon inside the pressure vessel of the normal amount of change △ P _{C, 0} to obtain an index value of vascular endothelial vasodilator function ( FMD _C ), as shown in the formula (1), and the index value of the vascular endothelial cell expansion function is displayed on the screen 9. In addition, the measurement process may be repeated, and the processor 7 may obtain a normal period of the blood vessel and the blood vessel after calculating the amount of change in the balloon internal pressure of each cardiac cycle during the normal period of the blood vessel and the vascular reactive hyperemia period. A waveform of relative vessel volume change over time during reactive hyperemia, and a waveform of changes in vessel volume over time can be displayed on screen 9, and the processor calculates each period of vascular reactive hyperemia After the change in the intravesical pressure of the cardiac cycle is divided by the average value of the change in the intravesical pressure of the normal phase of the blood vessel, a waveform of the endothelial cell expansion function index value which changes with time during the vascular reactive hyperemia is obtained, and A waveform of endothelial cell expansion function index during vascular reactive hyperemia over time can be displayed on the screen 9.

The physical meaning of FMD _C refers to the index value of the vascular endothelial cell expansion function estimated by the balloon 5, and the physical value of the normal internal pressure change ΔP _{C, 0} refers to the intravascular balloon pressure before the high pressure occlusion. The maximum amount of oscillation variation.

As shown in FIGS. 5 and 6, when an airbag having a width L is wrapped around the upper arm, the internal pressure of the airbag 5 is in a non-linear relationship with the volume, but when the internal pressure of the airbag is maintained at a low pressure, And when the internal pressure changes or the oscillation is extremely small, it is obvious that the relationship between the internal pressure of the balloon and the volume within the narrow range can be regarded as approximately linear. The blood in the radial artery and the tissue between the radial artery and the balloon are incompressible substances, and the air in the airbag bag is a Compressable substance. When an airbag with a fixed low air pressure (between 30 and 60 mm Hg) is wrapped around the upper arm, the volume of the radial artery is at the maximum contraction point (A1) due to the interaction between the balloon and the artery (Fig. 6). The volume change (ie ΔVa=Va,max-Va,min) generated at the maximum expansion point (A2) is directly reflected in the volume change of the airbag 5, that is, the maximum expansion point (B1) of the airbag volume should be The maximum contraction point relative to the blood vessel, and the maximum contraction point (B2) of the balloon volume should be relative to the maximum expansion point of the radial artery, so a certain proportion of the radial artery volume change will be reflected in the volume change of the balloon (△ Vc = Vc, max - Vc, min), as in equation (2).

Δ Vc = α (Δ Va ) .....................................(2)

Where α is a proportional constant between 0 and 1. Since the volume fluctuation amount (ΔPc) and the volume variation amount are small in the case of the airbag 5 having a low internal pressure, the relationship between the pressure fluctuation amount (ΔPc) and the volume variation amount can be regarded as a proportional relationship, as in the equation (3).

Where Cc is the compliance of the airbag 5 at this low pressure, and within this narrow range of variation, Cc can be regarded as a fixed value.

ΔV _C is the maximum oscillation variation of the intravesical pressure during the reactive hyperemia period after the blockage of the brachial artery. By substituting ΔP _C and ΔP _C,0 in the formula (1) according to the formula (3), the formula (4) can be derived.

Further, after ΔV _C and ΔV _C,0 in the formula (4) are substituted according to the formula (2), it is obtained:

Therefore, it can be known from the formula (5) that the index value of the vascular endothelial cell expansion function counted by the balloon 5 is actually equivalent to the rate of change of the radial artery volume before and after the blockage. If the volume of the radial artery fluctuation in the formula (5) is expressed by the diameter, the formula (6) can be derived.

Where L is the width of the balloon bag, D _0,max is the maximum diameter of the radial artery in the normal state, D _0,min is the minimum diameter of the radial artery in the normal state, and Dmax is the largest during the reactive hyperemia of the radial artery after obstruction. Diameter, and Dmin is the smallest diameter of the radial artery during reactive hyperemia after occlusion. Dividing the denominator of formula (6) by (Lπ/4) can be simplified as equation (7)

It is assumed that during the normal state and during reactive hyperemia after occlusion, the difference in the minimum diameter of the blood vessel is small and negligible (ie D _0,min ≒D _min ); it is also assumed that D ² _0,max >>D ² _0,min (only reasonable if there is a large change in diameter), then equation (7) can be simplified as equation (8)

Where D ₀ is the maximum diameter of the radial artery under normal conditions, and D is the largest diameter of the radial artery during reactive hyperemia after obstruction.

Further, the following formula (9) is a method for calculating the endothelial cell expansion function index value (FMD _U ) of the upper brachial artery (or arm artery) by using high-frequency ultrasonic waves.

Comparing equation (9) with equation (8), equation (8) can be converted to equation (10).

As can be seen from the formula (10), the value of the endothelial cell expansion function index measured by the balloon 5 is much larger than the value of the endothelial cell expansion function index measured by ultrasound.

In summary, the present invention has the following advantages:

(1) The airbag 5 is used to obtain the required value, which can reduce the cost compared to the method of using ultrasonic waves.

(2) The invention can be operated without a skilled doctor or technician, and can be used in a general place, which can increase the popularity.

(3) From the formula (10), the balloon 5 method has higher sensitivity when measuring the endothelial cell expansion function index value than the ultrasonic method.

The above is only the preferred embodiment of the present invention, and the scope of the invention is not limited thereto, that is, the simple equivalent changes and modifications made by the scope of the invention and the description of the invention are All remain within the scope of the invention patent.

1‧‧‧Steps of normal internal pressure

11‧‧‧Enable steps

12‧‧‧Steps for boosting

13‧‧‧Steps for measuring signals

14‧‧‧Compare steps

15‧‧‧Steps to suspend

16‧‧‧Steps to stop pressurization

2‧‧‧Steps for blocking internal pressure

21‧‧‧Enable steps

22‧‧‧Steps for boosting

23‧‧‧Steps for measuring signals

24‧‧‧Compare steps

25‧‧‧Steps to suspend

26‧‧‧Steps to stop pressurization

27‧‧‧Steps for relieving pressure signals

28‧‧‧Steps for pressure relief

29‧‧‧Steps to get hyperemia

3‧‧‧Steps for calculating the difference value

4‧‧‧Steps to calculate the expansion value

5‧‧‧Airbag

6‧‧‧Pneumatic adjustment circuit

61‧‧‧Digital Analog Converter

62‧‧‧ pump controller

63‧‧‧

7‧‧‧ Processor

8‧‧‧Pneumatic sensing circuit

81‧‧‧ Sensor

82‧‧‧Bandpass filter

83‧‧‧Amplifier

84‧‧‧ analog digital converter

9‧‧‧ screen

Figure 1 is a functional block diagram of a preferred embodiment of the present invention;

Figure 2 is a flow chart of the preferred embodiment;

Figure 3 is a flow chart of the sub-steps in the first step;

Figure 4 is a flow chart of the sub-steps in the second step;

Figure 5 is a schematic cross-sectional view of the airbag surrounding the upper arm;

Figure 6 is a schematic illustration of the interaction of the balloon with the radial artery.

5‧‧‧Airbag

6‧‧‧Pneumatic adjustment circuit

61‧‧‧Digital Analog Converter

62‧‧‧ pump controller

63‧‧‧

7‧‧‧ Processor

8‧‧‧Pneumatic sensing circuit

81‧‧‧ Sensor

82‧‧‧Bandpass filter

83‧‧‧Amplifier

84‧‧‧ analog digital converter

9‧‧‧ screen

Claims (10)

A method for measuring the function of endothelial cell expansion, which measures the expansion function of vascular endothelial cells by applying pressure to one of the limbs of a subject, and includes the following steps: setting the internal gas pressure of the balloon to a low pressure a preset value for applying pressure to one of the limbs of the subject; measuring the air pressure in the airbag to obtain a change in the internal pressure of the balloon during a normal period of the blood vessel, wherein the change in the internal pressure of the balloon during the normal period of the blood vessel is obtained The steps include: finding a relative high value and a very low value of the air pressure value in each cardiac cycle during a normal state of the blood vessel; calculating the relative extremely high value and the extremely low value of the air pressure value in each cardiac cycle Obtaining the difference value of the internal pressure of the balloon in each cardiac cycle; finding out the difference between the intracardial pressure of the heartbeat in each of the cardiac cycles, and the difference between the internal pressure of the majority of the cardiac cycles; The value is used as the amount of change in the internal pressure of the balloon during the normal period of the blood vessel; the internal gas pressure of the balloon is set to a preset value of high pressure to apply pressure to one of the limbs of the subject; and the bladder is then released to the pressure After the preset value of the low pressure, the air pressure in the airbag is measured to obtain the change of the intravesical pressure of the blood vessel during the vascular reactive hyperemia period; the change of the intravesical pressure of the vascular reactive hyperemia period and the intravascular pressure of the normal period of the blood vessel are compared The amount of change is obtained to obtain a difference value; and the difference value is divided by the change amount of the intravesical pressure of the normal period of the blood vessel to obtain an index value of the expansion function of the vascular endothelial cell, as follows: Among them, FMD _C is an index value of the vascular endothelial cell expansion function, ΔP _C - ΔP _{C, 0} is the difference value, and ΔP _{C, 0} is the amount of change in the balloon internal pressure during the normal period of the blood vessel. The method for measuring an endothelial cell expansion function according to claim 1, wherein the step of setting the low pressure preset value comprises: increasing an internal gas pressure of the airbag by 0; performing air pressure in the airbag Measure to obtain a pressure value; compare whether the air pressure value reaches the low pressure preset value; and if so, stop pressurizing the air bag. The method for measuring endothelial cell expansion function according to claim 1, wherein the optimal range of the blood vessel normal period is 3 to 30 seconds. According to the method for measuring the function of endothelial cell expansion according to claim 1, wherein the relatively stable and continuous majority of the intracardial pressure difference value of the cardiac cycle is relatively stable and continuous during the normal state of the blood vessel. 3 to 15 cardiac cycle air pressure difference values. The method for measuring an endothelial cell expansion function according to claim 1, wherein the step of setting the high pressure preset value comprises: increasing an internal gas pressure of the airbag from the low pressure preset value; The internal air pressure is measured to obtain a pressure value; whether the air pressure value reaches the high pressure preset value; If so, the bladder is stopped from being pressurized. The method for measuring the function of endothelial cell expansion according to claim 1, wherein when the internal pressure of the balloon reaches the preset value of the high pressure, the blood vessel in one of the limbs of the subject is blocked at a high pressure. During the time, the blood cannot flow, and then the pressure is released. The method for measuring endothelial cell expansion function according to claim 6 of the patent application, wherein the optimal range of the high pressure blocking time is 3 to 5 minutes. According to the method for measuring the function of endothelial cell expansion according to claim 1, wherein, after releasing the pressure to the preset value of the low pressure, the air pressure in the balloon is measured to obtain the balloon in the vascular reactive hyperemia period. The step of changing the amount of pressure includes: decreasing the internal gas pressure of the airbag by the preset value of the high pressure; measuring the air pressure in the airbag to obtain a pressure value; comparing whether the air pressure value reaches the low pressure preset value; Stopping the pressure release of the airbag; and finding the extremely high value and the extremely low value of the air pressure value with respect to each cardiac cycle during the vascular reactive hyperemia time after the airbag is released to the preset value of the low pressure; Calculate the extremely high value and the extremely low value of the air pressure value in each cardiac cycle to obtain the difference of the internal pressure of the airbag in each cardiac cycle; find out the large and continuous majority of the intracardial airbags in the difference of the intracardial pressure of each cardiac cycle The difference value of the pressure; and the average value of the difference in the internal pressure of the majority of the cardiac cycle is used as the amount of change in the internal pressure of the balloon during the vascular response. The method for measuring the function of endothelial cell expansion according to claim 8 of the patent application, wherein the optimal range of the vascular reactive hyperemia is 3 to 15 minutes. According to the method for measuring the function of endothelial cell expansion according to claim 1, the blood vessel can be obtained after the amount of change in the intravesical pressure of each cardiac cycle during the normal phase of the blood vessel and the vascular reactive hyperemia period. The relative vascular volume change waveform during the normal period and during the vascular reactive hyperemia, and the change of the intravesical pressure of each cardiac cycle during the vascular reactive hyperemia is divided by the change of the intravesical pressure of the normal period of the vascular After the mean value of the amount, a waveform of the endothelial cell expansion function index value which changes with time during the vascular reactive hyperemia is obtained.