JP4187498B2 - Endothelial function test device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vascular endothelial function testing device for testing vascular endothelial function, and more particularly, to a vascular endothelial function testing device for testing vascular endothelial function based on a blood flow-dependent vasodilator reaction due to reactive hyperemia.
[0002]
[Prior art]
Vascular endothelial cells are a group of cells lining the artery, not only covering the inner wall of the blood vessel and separating the blood components from the living tissue, but also the size of the blood vessel and the elasticity and transmission of the blood vessel wall. It has the function of producing and releasing substances that control the properties and reactivity. And, since the vascular endothelial cell function decline is seen from the pre-stage of arteriosclerosis where arteriosclerosis has not yet begun, the arteriosclerosis is prevented or treated at an early stage by detecting this vascular endothelial cell function decline. be able to.
[0003]
As a method for examining vascular endothelial function, a method for noninvasively examining a blood flow-dependent vasodilation reaction due to reactive hyperemia using an ultrasonic device has become the mainstream. The blood flow-dependent vasodilatation reaction due to the above-mentioned reactive hyperemia is a reaction in which blood vessels are expanded once after a predetermined site in a living body is released, and then the blood vessels expand after releasing the blood transfusion. Occurs, and vascular endothelial cells are stimulated by the increase in blood flow, and a substance that expands the blood vessel diameter (nitrogen monoxide and similar compounds) is secreted from the blood vessel endothelial cells, resulting in a reaction that expands the blood vessel diameter. It is. When the vascular endothelial function is lowered, the secretion of a substance that expands the blood vessel diameter is small, and therefore the blood vessel diameter does not expand so much even if the blood transfusion is released. Therefore, vascular endothelial function can be examined by looking at the extent of expansion of the blood vessel diameter due to this reaction.
[0004]
As described above, the blood flow-dependent vasodilatation reaction is examined using an ultrasonic device. This method is described, for example, in Non-Patent Document 1, and images of an artery are continuously depicted using an ultrasonic probe, and the diameter of the blood vessel after cancellation of blood transfusion with respect to the diameter of the blood vessel before blood transduction is determined from the image. In this method, the maximum increase rate is calculated and the vascular endothelial function is examined based on the maximum increase rate. The maximum rate of increase is called% FMD (Flow mediated dilatation), and is about 10% for healthy individuals. When% FMD reaches 3 to 4%, it is arteriosclerosis (or soon becomes arteriosclerosis). Is likely).
[0005]
[Non-Patent Document 1]
Toshio Ozawa, Yoshiaki Masuda, “Pulse Wave Velocity”, 1st Edition, Medical View Inc., May 1, 2002, p.104-p.106
[0006]
[Problems to be solved by the invention]
However, the method for calculating% FMD by examining a blood flow-dependent vasodilator reaction using an ultrasonic device has the following problems. First, the biggest problem is that the above method has a large variation between inspectors and between inspection facilities, and there is a fluctuation of 2 to 3%. As mentioned above, about 10% is normal and 3-4% is considered abnormal, so fluctuations of 2-3% are a major problem. The cause of this fluctuation is that an ultrasonic probe must be placed perpendicular to the blood vessel, and that a technique is required to detect an accurate signal. Since the blood vessel diameter at the end of diastole of the heart at the time of the most blood vessel dilation must be determined, the time when the blood vessel diameter is determined will vary. Depending on the reason. Therefore, it takes a period of several months to acquire the technique of the measurement method, and the% FMD is reliable unless it is actually data of an inspector who has experienced a certain period (for example, about half a year) and a certain number of measurers. It is said that it cannot be done. In addition, the diameter of the blood vessel is about 5 mm, and it is necessary to detect an expansion of 10% or less of the blood vessel, that is, an expansion of 0.5 mm or less. There is also the problem of being.
[0007]
The present invention has been made against the background of the above circumstances, and its object is to test the vascular endothelial function with high reliability, and does not require skill in the inspection, and is inexpensive. It is to provide an inspection device.
[0008]
[First Means for Solving the Problems]
The first invention for achieving the above object is as follows: (a) a blood-feeding device that drives a artery at a predetermined site of a living body for a predetermined time or more; and (b) a blood-feeding site by the blood-feeding device. Also, the first pulse wave propagation information, which is pulse wave propagation information related to the speed at which the pulse wave propagates through the artery in the first section including the downstream part, and the first section are substantially symmetric with respect to the median plane. A pulse wave propagation information measuring device for sequentially measuring the second pulse wave propagation information, which is the pulse wave propagation information of the artery in the second section, and (c) before being driven by the blood drive device and by the blood drive device A vascular endothelial function testing device comprising propagation information difference calculation means for calculating a difference in propagation information between the first pulse wave propagation information and the second pulse wave propagation information after release of blood transfusion. .
[0009]
[Effect of the first invention]
According to this invention, the first pulse wave propagation information measured by the pulse wave propagation information measurement device after the blood transfusion is released by the blood drive device is obtained by expanding the blood vessel diameter by the blood flow-dependent vasodilation reaction after the blood transfusion is released. As a result, the first pulse wave propagation information measured before the blood pumping changes due to the influence of the decrease in the elastic modulus of the blood vessel wall. Since this first pulse wave propagation information varies from one beat to another due to the effects of blood pressure, heart rate, and other systemic factors that vary from one beat to another, the change due to the cancellation of the hemostasis is not clear. However, since the second pulse wave propagation information is the pulse wave propagation information of the second section that is substantially symmetric to the first section with respect to the median plane, one beat due to the influence of blood pressure, heart rate, and other systemic factors. Each change is substantially the same as the first pulse wave propagation information, and the propagation information difference calculated by the propagation information difference calculating means is a difference between the first pulse wave propagation information and the second pulse wave propagation information. The propagation information difference eliminates the influence of fluctuations in blood pressure, heart rate, and other systemic factors for each beat, and changes after the release of the blood transfusion are clarified. Therefore, if the vascular endothelial function is examined based on this propagation information difference, the vascular endothelial function can be examined with high reliability. Further, measurement of pulse wave propagation information does not require skill, and there is an advantage that the apparatus is inexpensive.
[0010]
[Other aspects of the first invention]
Here, preferably, the vascular endothelial function test apparatus is configured to calculate a difference between before and after that is a difference between a peak in propagation information difference after release of blood transfusion calculated by the propagation information difference calculation means and a propagation information difference before blood transfer. It further includes vascular endothelial function lowering determination means for determining a decrease in vascular endothelial function based on the absolute value being equal to or less than a preset criterion value. In this way, the vascular endothelial function is automatically determined.
[0011]
Preferably, the vascular endothelial function testing device further includes an output device for displaying a graph showing a temporal change of the propagation information difference calculated by the propagation information difference calculation means. When the blood vessel diameter expands most, a peak is formed in the graph showing the change in propagation information difference over time. Thus, when the change in propagation information difference over time is displayed in a graph on the output device, the blood vessel diameter is easily changed. The most expanded time can be determined.
[0012]
[Second means for solving the problem]
In the first aspect of the invention, the propagation information difference between the first pulse wave propagation information and the second pulse wave propagation information is calculated. However, even if the ratio is calculated instead of the propagation information difference, the above-described object is achieved. Can be achieved.
[0013]
That is, the second invention for achieving the above object is as follows: (a) a blood-feeding device for driving a artery at a predetermined site of a living body for a preset predetermined time; and (b) blood-feeding by the blood-feeding device. First pulse wave propagation information, which is pulse wave propagation information related to the speed at which the pulse wave propagates through the artery in the first section including the part downstream of the part, and the first section is substantially the same as the first section with respect to the median plane A pulse wave propagation information measuring device for sequentially measuring the second pulse wave propagation information, which is the pulse wave propagation information of the arteries in the symmetric second section, and (c) before and after being driven by the blood drive device A vascular endothelial function testing device, comprising: propagation information ratio calculation means for calculating a propagation information ratio between the first pulse wave propagation information and the second pulse wave propagation information after release of blood transfusion by the device It is.
[0014]
[Effect of the second invention]
According to this invention, the propagation information ratio calculated by the propagation information ratio calculation means is the ratio between the first pulse wave propagation information and the second pulse wave propagation information in the sections that are substantially in contrast to the median plane. In the propagation information ratio, the influence of fluctuations in blood pressure, heart rate, and other systemic factors for each beat is removed, and the change after the release of the blood transfusion is clarified. Therefore, if the vascular endothelial function is examined based on this propagation information ratio, the vascular endothelial function can be examined with high reliability. Further, as described above, measurement of pulse wave propagation information does not require skill, and there is an advantage that the apparatus is inexpensive.
[0015]
[Other aspects of the second invention]
In addition, the vascular endothelial function test apparatus according to the second aspect of the invention is preferably provided with a vascular endothelial function lowering determination means and an output device similar to those of the first aspect of the invention.
[0016]
That is, the vascular endothelial function test apparatus according to the second aspect of the present invention is preferably the difference between the peak in the propagation information ratio after cancellation of blood transfusion calculated by the propagation information ratio calculation means and the transmission information ratio before blood transmission. It further includes vascular endothelial function lowering determination means for determining a decrease in vascular endothelial function based on the absolute value of the difference being equal to or less than a preset determination reference value. In this way, the vascular endothelial function is automatically determined.
[0017]
Preferably, the vascular endothelial function testing device according to the second aspect of the present invention further includes an output device that graphically displays a change with time of the propagation information ratio calculated by the propagation information ratio calculation means. In this way, when the change in propagation information ratio with time is displayed in a graph on the output device, it is possible to easily determine the time point when the blood vessel diameter is most expanded.
[0018]
[Other aspects of the first and second inventions]
Preferably, both the first section and the second section have a heart at the upstream end, and the pulse wave propagation information measuring device detects a heartbeat synchronization signal generated from the heart of the living body. And measuring the first pulse wave propagation information and the second pulse wave propagation information using a heart beat synchronization signal detected by the heart beat synchronization signal detecting device. If the first pulse wave propagation information and the second pulse wave propagation information are measured based on the heart beat synchronization signal detected by one heart beat synchronization signal detection device in this way, it is attached to the living body to measure the pulse wave propagation information. The number of devices to be performed can be reduced.
[0019]
Preferably, the heartbeat synchronization signal detection device is an electrocardiograph that measures an action potential of a myocardium, and the first pulse wave propagation information and the second pulse wave propagation information are both pulse wave propagation times. . In this way, the pulse wave propagation information measuring device measures the first pulse wave propagation time and the second pulse wave propagation time based on the electrocardiogram, and the propagation information difference calculating means calculates the first pulse wave propagation time and A propagation time difference from the second pulse wave propagation time is calculated. The ECG has a sharp signal, so the reference point used to calculate the pulse wave propagation time can be accurately determined. On the other hand, the pulse wave propagation time causes blood to be ejected after the left ventricular myocardium begins to contract. However, since both the first pulse wave propagation time and the second pulse wave propagation time include a common precursor ejection time, the propagation time difference calculated by the propagation information difference calculating means is included. Is offset by the precursor time and is not affected by the precursor time. Therefore, the vascular endothelial function can be examined with high accuracy.
[0020]
In addition, preferably, the blood pumping device is configured to drive blood at the upper arm portion of the living body, and the first section is a section from the heart to the wrist on the side driven by the blood driving device. In this way, the first section includes a relatively long section on the downstream side of the blood-feeding site. In other words, since the first section includes a relatively long section in which the blood vessel expands due to the cancellation of the tourniquet, the first pulse wave propagation information has a relatively large amount of change after the release of the tourniquet. Therefore, the propagation information difference calculated by the propagation information difference calculating means also increases in the reliability of the vascular endothelial function test since the change after the blood transfusion is released before the blood transfusion is increased.
[0021]
The vascular endothelial function test can be performed by the following method regardless of whether or not the vascular endothelial function test apparatus is used. That is, the examination of the vascular endothelial function is performed by driving a predetermined part of a living body for a predetermined time or more, and before and after releasing the blood transfer, the first section including the downstream part of the blood-feeding part and the first section. First pulse wave propagation information and second pulse wave propagation information related to the speed at which the pulse wave propagates are calculated in a second section that is substantially symmetric with respect to the median plane, and the first pulse wave propagation information and the first pulse wave propagation information Inspection can be performed based on a propagation information difference which is a difference from the two-pulse wave propagation information.
[0022]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram for explaining the configuration of a vascular endothelial function testing device 10 to which the present invention is applied. FIG. 2 is a diagram illustrating cuff 14 and pressure pulse wave detection provided in the vascular endothelial function testing device 10 of FIG. It is a figure which shows the state with which the probe 18 was mounted | worn with the patient.
[0023]
As shown in FIG. 2, the cuff 14 is attached to one upper arm (here, the upper arm of the left arm) of the patient 12, and the two pressure pulse wave detection probes 18 are attached to the left and right wrists of the patient 12, respectively.
[0024]
As shown in FIG. 1, a pressure regulating valve 22 and a pressure sensor 24 are connected to the cuff 14 via a pipe 20, and the pressure regulating valve 22 is further connected to an air pump 28 via a pipe 26. The pressure regulating valve 22 regulates the pressure in the cuff 14 by regulating the high-pressure air generated by the air pump 28 and supplying the air into the cuff 14 or exhausting the air in the cuff 14.
[0025]
The pressure sensor 24 detects the pressure in the cuff 14 and supplies a pressure signal SP representing the pressure to the static pressure discriminating circuit 30. The static pressure discriminating circuit 30 includes a low-pass filter, and discriminates a cuff pressure signal SC representing a steady pressure included in the pressure signal SP, that is, a compression pressure of the cuff 12 (hereinafter, this pressure is referred to as a cuff pressure PC). The cuff pressure signal SC is supplied to the electronic control unit 32 via an A / D converter (not shown).
[0026]
The plurality of electrodes 16 are attached to a predetermined site of the patient 12 in order to measure an electrocardiogram. The method for deriving the electrocardiogram is not particularly limited, and any guidance method such as bipolar limb guidance or chest guidance may be used. The plurality of electrodes 16 are connected to an electrocardiograph 34. The electrocardiograph 34 amplifies an electrocardiogram signal SE derived from the electrode 16 and sends it to an electronic control unit 32 via an A / D converter (not shown). Supply. The electrocardiogram signal SE represents an action potential of the myocardium, that is, an electrocardiogram.
[0027]
The two pressure pulse wave detection probes 36 have the same configuration. As shown in detail in FIG. 3, a sensor housing 38 that forms a container, a case 40 that accommodates the sensor housing 38, and a sensor housing 38. A screw shaft 44 that moves the sensor housing 38 in the width direction of the radial artery 42 by being screwed and rotationally driven, and a motor (not shown) that is housed in the case 40 and that rotationally drives the screw shaft 44. And a drive unit 46. A mounting band 48 is attached to the case 40.
[0028]
The thus configured pressure pulse wave detection probe 36 is detachably attached to the wrist 52 by the mounting band 48 with the open end of the sensor housing 38 facing the body surface 50.
[0029]
Inside the sensor housing 38, a pressure pulse wave sensor 54 is provided so as to be able to move relative to the sensor housing 38 via a diaphragm 56 and to protrude from the open end of the sensor housing 38. A pressure chamber 57 is formed by the diaphragm 56 and the like. As shown in FIG. 1, high pressure air is supplied from the air pump 58 through the pressure regulating valve 60 into the pressure chamber 57, so that the pressure pulse wave sensor 54 is in the pressure chamber 57. The body surface 50 is pressed with a pressing force HDP (Hold Down Pressure) corresponding to the internal pressure.
[0030]
The sensor housing 38 and the diaphragm 56 constitute a pressing device 62 that presses the pressure pulse wave sensor 54 toward the radial artery 42, and the motor (not shown) of the screw shaft 44 and the drive unit 46 is the pressure pulse wave sensor 54. The width direction moving device 64 is configured to move the pressing position pressed toward the body surface 50 in the width direction of the radial artery 42.
[0031]
On the pressing surface 66 of the pressure pulse wave sensor 54, as shown in FIG. 4, a large number of semiconductor pressure sensing elements (hereinafter simply referred to as pressure sensing elements) E are parallel to the radial direction of the radial artery 42, that is, the screw shaft 44. In the moving direction of the pressure pulse wave sensor 54, the pressure pulse wave sensor 54 is arranged so as to be longer than the diameter of the radial artery 42 and at a constant interval (for example, 0.2 mm interval).
[0032]
When the thus configured pressure pulse wave detection probe 36 is pressed from the body surface 50 of the wrist 52 toward the radial artery 42, the pressure pulse wave sensor 54 generates the pressure pulse wave sensor 54 from the radial artery 42 to generate the body surface 50. As shown in FIG. 1, a pressure pulse wave signal SM representing the radial artery wave RW is supplied to the electronic control unit 32 via an A / D converter (not shown). In the following description, the pressure pulse wave signal SM output from the pressure pulse wave sensor 54 attached to the left wrist is referred to as the left pressure pulse wave signal SM._L, Its left pressure pulse wave signal SM_LThe radial artery wave RW represented by the left radial artery wave RW_LThe pressure pulse wave signal SM output from the pressure pulse wave sensor 54 attached to the right wrist is converted into the right pressure pulse wave signal SM._R, Its right pressure pulse wave signal SM_RThe radial artery wave RW represents the right radial artery wave RW_RThat's it.
[0033]
The electronic control unit 34 includes a CPU 68, a ROM 70, a RAM 72, and a so-called microcomputer having an I / O port (not shown). The CPU 68 uses a storage function of the RAM 72 in accordance with a program stored in the ROM 70 in advance. However, by executing signal processing, a drive signal is output from the I / O port, the pressure regulating valve 22 and the air pump 28 are controlled via a drive circuit (not shown), the cuff pressure PC is controlled, and the air A drive signal is output to the pump 58 and the pressure regulating valve 60 through a drive circuit (not shown) to adjust the pressure in the pressure chamber 57. Further, the CPU 68 calculates a pulse wave propagation time PCT (Pulse conduction time) and a propagation time difference ΔPCT by executing arithmetic processing based on a signal supplied to the electronic control unit 34, and the calculated pulse wave propagation time PCT. The propagation time difference ΔPCT is displayed on the display 74 functioning as an output device.
[0034]
FIG. 5 is a functional block diagram for explaining a main part of the control function of the CPU 68 in the vascular endothelial function testing device 10 of FIG. The cuff pressure control means 60 functioning as a blood drive control means controls the pressure regulating valve 22 and the air pump 28 while determining the cuff pressure PC based on the cuff pressure signal SC supplied from the static pressure discriminating circuit 30. , Cuff pressure PC, maximum blood pressure BP at cuff 14 wearing site_SYSThe blood pressure is rapidly increased to a preset tourniquet pressure value P1 (for example, 250 mmHg), and then the cuff pressure PC is maintained for a predetermined time (for example, 5 minutes) determined based on an experiment in advance. The cuff pressure PC is exhausted to atmospheric pressure. In the present embodiment, the cuff 14 and the pressure regulating valve 22 for controlling the cuff pressure PC, the air pump 28, the pressure sensor 24, and the cuff pressure control means 80 constitute a blood driving device 82.
[0035]
The optimum pressing position control means 84 has an arrangement position of an element (hereinafter referred to as a maximum pressure detecting element EM) for detecting the maximum pressure among the plurality of pressure sensitive elements E provided in the pressure pulse wave sensor 54. It is determined whether or not a pressing position update condition is satisfied on the condition that it is located within a predetermined number or a predetermined distance from the end of the position. When the pressing position update condition is satisfied, the following pressing position update operation is executed. That is, in the pressing position update operation, the pressure pulse wave sensor 54 is once separated from the body surface 50, the pressing device 62 and the pressure pulse wave sensor 54 are moved by a predetermined distance by the width direction moving device 64, and then the pressing device 62 The pressure pulse wave sensor 54 is pressed with a relatively small first pressing force HDP1, and it is determined whether or not the pressing position update condition is satisfied again in this state until the pressing position update condition is not satisfied. More preferably, the above-described operation and determination are performed until the maximum pressure detection element EM is located at the approximate center of the arrangement position. The predetermined number or the predetermined distance from the end of the array in the pressing position update condition is determined based on the diameter of the artery (radial artery 42 in the present embodiment) pressed by the pressure pulse wave sensor 54. It is set to 1/4 of the diameter.
[0036]
After the pressure pulse wave sensor 54 is positioned at the optimum pressing position by the optimum pressing position control means 84, the pressing force control means 86 changes the pressing force HDP of the pressure pulse wave sensor 54 by the pressing device 62 to a predetermined pressing force range. Within a predetermined pressing force range or continuously at a relatively slow constant speed. Then, the optimum pressing force HDPO is determined based on the radial artery wave RW obtained in the changing process of the pressing force HDP, and the pressing force HDP of the pressure pulse wave sensor 54 by the pressing device 62 is maintained at the optimum pressing force HDPO. Here, the optimum pressing force HDPO is a pressing force in which the side pressed by the pressure pulse wave sensor 54 of the blood vessel wall of the radial artery 42 becomes substantially flat by the pressing force HDP of the pressure pulse wave sensor 54. As shown in FIG. 6, the radial artery wave RW obtained from the maximum pressure detecting element EM of the pressure pulse wave sensor 54 in the process of continuously increasing the pressing force HDP in a range sufficiently including the optimal pressing force HDPO. In the two-dimensional graph showing the magnitude and the pressing force HDP of the pressure pulse wave sensor 54, the center of the flat portion formed by the curve (broken line in FIG. 6) connecting the lower peak value (rising point) RWmin of the radial artery wave RW is shown. The pressing value is within a predetermined range as the center.
[0037]
The pulse wave propagation time calculation means 88 functioning as pulse wave propagation information calculation means is sequentially supplied from the electrocardiogram signal SE sequentially supplied from the electrocardiograph 34 and the maximum pressure detection element EM of the two pressure pulse wave sensors 54, respectively. Right pressure pulse wave signal SM_RAnd left pressure pulse wave signal SM_LBased on the right pulse wave propagation time PCT, which is the time for the pulse wave to propagate from the heart to the right wrist_R, And the left pulse wave propagation time PCT, which is the time for the pulse wave to propagate from the heart to the left wrist_LAre calculated respectively. That is, from the time at which a predetermined portion of the electrocardiogram represented by the electrocardiogram signal SE (R wave in this embodiment) is detected, the right pressure pulse wave signal SM_RRepresents the right radial artery wave RW_ROf the right pulse wave propagation time PCT is calculated as the time difference until a predetermined part of (in this embodiment, the rising point) is detected._RThe left pressure pulse wave signal SM is calculated from the time when the predetermined part (R wave) of the electrocardiogram represented by the electrocardiogram signal SE is detected._LRepresents the left radial artery wave RW_LThe time difference until the predetermined part (rising point) is detected, the left pulse wave propagation time PCT_LCalculate as Strictly speaking, the pulse wave propagation time PCT calculated based on the electrocardiogram in this way is the time when the blood wave starts to contract from the heart to the right (left) wrist until the heart wave starts to contract. This is the time added to the precursor delivery time until the patient is driven.
[0038]
The pulse wave propagation time calculation means 88 controls the cuff pressure from a predetermined time (5 minutes before in this embodiment) before the cuff pressure is controlled by the cuff pressure control means 80 and the cuff 14 drives the left upper arm. This right pulse wave propagation time PCT until a predetermined time (5 minutes in this example) has passed since the release of_RAnd left pulse wave propagation time PCT_LIs calculated for each beat. However, left rib arterial wave RW while driving with left upper arm_LDoes not occur, so the left pulse wave propagation time PCT during that time_LIs not calculated. And the calculated right pulse wave propagation time PCT_RAnd left pulse wave propagation time PCT_LIs displayed on the display 56 as a graph. The left pulse wave propagation time PCT_LIs the first pulse wave propagation information because it includes a downstream portion of the portion driven by the cuff 14, and corresponds to the first section from the heart to the left wrist. The second interval is from the heart to the right wrist, and the right pulse wave propagation time PCT_RCorresponds to the second pulse wave propagation information. In this embodiment, the electrocardiograph 34, the two pressure pulse wave sensors 54, the optimum pressing position control means 84, the pressing force control means 86, and the pulse wave propagation time calculation means 88 are included in the pulse wave propagation information measuring device 90. Function as.
[0039]
Comparing the first section and the second section, the first section is from the heart to the left wrist, and the second section is from the heart to the right wrist. They are almost symmetrical with each other. Since the heart is located slightly to the left of the median plane, the two sections are not completely symmetric with respect to the median plane.
[0040]
The propagation time difference calculation means 92 functioning as the propagation information difference calculation means is the left pulse wave propagation time PCT calculated for each beat by the pulse wave propagation time calculation means 88._LTo right pulse wave propagation time PCT_RBy subtracting, the propagation time difference ΔPCT, which is the difference between two propagation times PCT based on the same pulsation, is calculated for each beat, and the change over time of the propagation time difference ΔPCT calculated for each beat is displayed on the display 74 as a graph. To do.
[0041]
7 to 10 show the right pulse wave propagation time PCT calculated by the pulse wave propagation time calculation means 88._R, Left pulse wave propagation time PCT_L, And the propagation time difference ΔPCT calculated by the propagation time difference calculation means 92 are shown side by side, and FIGS. 7 to 10 are measured values for different patients, and the blood transfusion period is from 5 minutes to 10 minutes of the graph. 5 minutes. As shown in FIGS. 7 to 10, the left pulse wave propagation time PCT_LAlthough there are individual differences in the degree of fluctuation, the fluctuation varies from beat to beat due to the influence of fluctuation in blood pressure, heart rate, and other systemic factors. Therefore, the left pulse wave propagation time PCT due to the cancellation of blood pressure_LThe change in the left pulse wave propagation time PCT is not clear_LThe right pulse wave propagation time PCT of the first section, which is the measurement section of the second section, and the second section, which is substantially symmetrical with respect to the median plane_RThe fluctuation for each beat is the left pulse wave propagation time PCT_LIs substantially the same. For this reason, the propagation speed difference ΔPCT is free from fluctuation for each beat due to the influence of blood pressure, heart rate, and other systemic factors.
[0042]
Before describing the examination of the vascular endothelial function based on the propagation speed difference ΔPCT, first, the change in the pulse wave propagation time PCT due to the cancellation of blood transfusion will be described based on the Moens-Korteweg equation shown in Equation 1.
(Formula 1) PWV = (Eh / 2ρR)^1/2
In Equation 1, E is the Young's modulus, h is the thickness of the blood vessel wall, ρ is the blood density, and R is the blood vessel radius.
This equation is a well-known equation for the pulse wave propagation velocity PWV, and Equation 2 can be derived from the relationship between the pulse wave propagation velocity PWV and the pulse wave propagation time PCT.
(Formula 2) PCT = D / PWV = D (2ρR)^1/2/ (Eh)^1/2
In Equation 2, D is the propagation distance.
From Equation 2, it can be seen that the pulse wave propagation time PCT increases as the blood vessel radius R increases and the elastic modulus E decreases.
[0043]
If the vascular endothelial function is normal, the blood vessel dilates due to a blood flow-dependent reaction after the release of blood pressure, and the elastic modulus decreases, so the pulse wave propagation time PCT increases (slows). However, if the vascular endothelial function is lowered, the blood vessel does not expand so much even if the blood transfusion is released, so the pulse wave propagation time PCT does not increase so much. Therefore, left pulse wave propagation time PCT_LThe vascular endothelial function can be evaluated by observing the degree of increase due to the cancellation of the blood transfusion, but as shown in FIGS. 7 to 10, the left pulse wave propagation time PCT_LIt is difficult to judge the degree of increase due to the cancellation of thrush. However, since the fluctuation of the propagation time difference ΔPCT is eliminated for each beat, the increase of the pulse wave propagation time due to the cancellation of the blood pumping is clear.
[0044]
There are various methods for evaluating the degree of change in the propagation time difference ΔPCT due to the cancellation of the blood transfusion. For example, the amount of increase in the peak of the propagation time difference ΔPCT after the cancellation of the blood pressure relative to the propagation time difference ΔPCT before the blood pressure is increased. Evaluation can be made based on the increase rate of the peak of the propagation time difference ΔPCT after the release of blood transfusion with respect to the propagation time difference ΔPCT. If the increase amount or increase rate is large, it can be determined that the vascular endothelial function is normal. 7 to 10, it can be determined that the patients of FIGS. 7 to 9 have normal vascular endothelial function and the patient of FIG. 10 has abnormal vascular endothelial function.
[0045]
Returning to FIG. 5, the vascular endothelial function lowering determination means 94 determines a peak value from the propagation time difference ΔPCT after the release of blood transfusion calculated by the propagation time difference calculation means 92, and the propagation time difference before the start of blood transfusion from the peak value. By subtracting ΔPCT, calculate the difference between before and after propagation of the propagation time difference ΔPCT, or by dividing the peak value by the propagation time difference ΔPCT before starting the blood transfusion, before and after the propagation of the propagation time difference ΔPCT. The front-to-back ratio is calculated (note that the front-to-back difference and the front-to-back ratio are always positive values). Then, when the front-back difference or front-back ratio is equal to or less than a judgment reference value set based on an experiment in advance, it is determined that the vascular endothelial function is lowered, and characters or symbols indicating that are displayed on the display 74. To display. As the propagation time difference ΔPCT before the start of blood transfusion, a value at a predetermined point (for example, immediately before the start of blood transfusion) may be used. However, in order to eliminate the fluctuation, in this embodiment, the value before the start of blood transfusion is used. An average value for a predetermined time (for example, 3 minutes) is used.
[0046]
FIGS. 11 and 12 are flowcharts showing the main part of the control operation of the CPU 68 shown in the functional block diagram of FIG. 5, FIG. 11 shows a signal collection routine, and FIG. 12 shows a signal calculation routine.
[0047]
In FIG. 11, first, in step SA <b> 1 (hereinafter, step is omitted), the arrangement position of the maximum pressure detection element EM among the pressure sensitive elements E arranged on the pressing surface 66 of the pressure pulse wave sensor 54 is the arrangement. It is determined whether or not a pressing position update condition (APS activation condition) that satisfies whether the position is within a predetermined number or a predetermined distance from the end is satisfied. If this determination is negative, SA3 and later are executed.
[0048]
On the other hand, if the determination of SA1 is affirmative, that is, if the position where the pressure pulse wave sensor 54 is attached to the radial artery 42 is inappropriate, an APS control routine of SA2 corresponding to the optimum pressing position control means 84 is executed. To do. In this APS control routine, the pressure detection element E that detects the maximum amplitude among the pressure detection elements E of the pressure pulse wave sensor 54 by controlling the width direction moving device 64 is an array of the pressure detection elements E. The optimum pressing position is determined so as to be approximately the center position, and the pressure detecting element E is set to the maximum pressure detecting element EM. The pressure pulse wave signal SM in the following description means the pressure pulse wave signal SM detected by the maximum pressure detecting element EM determined in SA2.
[0049]
When the determination of SA1 is negative or when the above SA2 is executed, an HDP control routine of SA3 corresponding to the pressing force control means 86 is subsequently executed. That is, by controlling the pressure regulating valve 60, the pressing force HDP of the pressure pulse wave sensor 54 is continuously increased, and the pressing force that maximizes the amplitude of the radial artery wave RW detected by the maximum pressure detecting element EM in the process. Is determined as the optimum pressing force HDPO, and the pressing force HDP of the pressure pulse wave sensor 54 is held at the optimum pressing force HDPO.
[0050]
In the subsequent SA4, the electrocardiogram signal SE and the right pressure pulse wave signal SM at every predetermined sampling period._R, Left pressure pulse wave signal SM_LIs read. In SA5, it is determined whether or not 5 minutes have elapsed since the start of signal reading in SA4. When the determination of SA5 is negative, the electrocardiogram signal SE and the right pressure pulse wave signal SM are obtained by repeatedly executing SA4._R, Left pressure pulse wave signal SM_LContinue reading.
[0051]
On the other hand, when the determination of SA5 is affirmed, in the subsequent SA6, the cuff pressure PC is controlled by controlling the air pump 28 and the pressure regulating valve 22 while determining the cuff pressure PC based on the cuff pressure signal SC. The blood pressure of the left upper arm is started by controlling the blood pressure value P1.
[0052]
In the subsequent SA7, the electrocardiogram signal SE and the right pressure pulse wave signal SM at every predetermined sampling period._RIs read. In the subsequent SA8, it is determined whether or not the elapsed time from the start of blood feeding has passed 5 minutes. If this determination is negative, the electrocardiogram signal SE and the right pressure pulse wave signal SM are repeated by repeating SA7._RWhen the determination of SA8 is affirmed, the air pump 28 is stopped and the pressure regulating valve 22 is controlled to discharge the cuff pressure PC to the atmospheric pressure and release the blood pressure. .
[0053]
Then, in the subsequent SA10, as in the SA4, the electrocardiogram signal SE and the right pressure pulse wave signal SM at every predetermined sampling period._R, Left pressure pulse wave signal SM_LIn the subsequent SA11, it is determined whether or not 5 minutes have elapsed since the start of reading of the signal in SA10 after the release of blood pressure. If this determination is negative, the electrocardiogram signal SE and the right pressure pulse wave signal SM are obtained by repeatedly executing the SA10._R, Left pressure pulse wave signal SM_LIs affirmed, the signal acquisition routine is terminated and the signal calculation routine of FIG. 12 is executed.
[0054]
In the signal calculation routine shown in FIG. 12, first, in SB1, in the electrocardiogram represented by the electrocardiogram signal SE read in SA4, SA7, SA10, the detection time of the R wave is determined for each beat, and in SB2, SA4, Left pulse wave signal SM read at SA7 and SA10_LRepresents the left radial artery wave RW_LIs determined for each beat, and in the subsequent SB3, the right pulse wave signal SM read in SA4, SA7, SA10_RRepresents the right radial artery wave RW_RDetermine the starting point of each beat.
[0055]
In the subsequent SB4, the detection time of each R wave of the electrocardiogram determined in SB1 and each left radial artery wave RW determined in SB2_LThe time difference from the detection time of the rise point of the left pulse wave propagation time PCT_LIn the following SB5, the detection time of each R wave of the electrocardiogram determined in SB1 and each right radial artery wave RW determined in SB3_RThe time difference from the detection time of the rising point of_RAs per beat.
[0056]
Then, in the subsequent SB6 corresponding to the propagation time calculation means 92, the left pulse wave propagation time PCT calculated in SB4_LPCT propagation time PCT calculated from SB5_RBy subtracting, the propagation time difference ΔPCT for 5 minutes before and after the release of blood transfusion is calculated every beat.
[0057]
In subsequent SB7, the left pulse wave propagation time PCT calculated in SB4 to SB6 above._L, Right pulse wave propagation time PCT_RThe time-dependent change of the propagation time difference ΔPCT is displayed in a graph as illustrated in FIGS.
[0058]
Subsequently, SB8 to SB12 corresponding to the vascular endothelial function decrease determining means 94 are executed. First, in SB8, the average value of the propagation time difference ΔPCT for 3 minutes before the start of blood transduction among the propagation time difference ΔPCT for 5 minutes before the blood transfusion calculated in SB6 is calculated, and in the subsequent SB9, after the blood transfusion cancellation calculated in SB6 The peak at the propagation time difference ΔPCT is determined. Then, in the subsequent SB10, by subtracting the average value of the propagation time difference ΔPCT for 3 minutes before the blood transduction calculated in SB8 from the peak of the propagation time difference ΔPCT after the cancellation of the blood transfusion determined in SB9, the difference between before and after the propagation time difference ΔPCT is calculated. calculate.
[0059]
In the subsequent SB11, when the difference in front and back of the propagation time difference ΔPCT calculated in SB10 is equal to or less than a preset determination reference value, it is determined that the vascular endothelial function is lowered, and the difference in the front and back is determined as the above determination. If it is larger than the reference value, it is determined that the vascular endothelial function is normal, and a message representing the determination result is displayed on the display 74 in SB12.
[0060]
According to the above-described embodiment, the left pulse wave propagation time PCT measured by the pulse wave propagation information measuring device 90 after releasing the blood pressure by the blood pressure device 82._LIs the left pulse wave propagation time PCT measured before blood transfusion due to the increase in blood flow and the expansion of blood vessel diameter due to the cancellation of blood transfusion._LIncrease against. This left pulse wave propagation time PCT_LSince it varies from beat to beat due to the effects of blood pressure, heart rate, and other systemic factors that vary from beat to beat, the change due to the cancellation of the hemostasis is not clear. However, right pulse wave propagation time PCT_RIs the pulse wave propagation time PCT of the second section, which is approximately symmetrical with the first section with respect to the median plane, so the fluctuation of each beat due to the influence of blood pressure, heart rate, and other systemic factors is the left pulse wave Propagation time PCT_LThe propagation time difference ΔPCT calculated by the propagation time difference calculating means 92 (SB6) is the left pulse wave propagation time PCT._LAnd right pulse wave propagation time PCT_RTherefore, the propagation time difference ΔPCT is free from the influence of fluctuations in blood pressure, heart rate, and other systemic factors for each beat, and changes after the release of the tourniquet with respect to before the tourniquet are clarified. Therefore, if the vascular endothelial function is examined based on this propagation time difference ΔPCT, the vascular endothelial function can be examined with high reliability. Further, the measurement of the pulse wave propagation time PCT has the advantages that it does not require skill and the apparatus is inexpensive.
[0061]
Further, according to the above-described embodiment, the peak in the propagation time difference ΔPCT after the tourniquet release calculated by the propagation time difference calculation unit 92 (SB6) by the vascular endothelial function decrease determination unit 94 (SB8 to SB12) The decrease in the vascular endothelial function is automatically determined based on the fact that the difference between before and after the propagation time difference ΔPCT is equal to or less than a preset criterion value.
[0062]
In addition, according to the above-described embodiment, the display 74 for displaying the change over time of the propagation time difference ΔPCT calculated by the propagation time difference calculation means 92 (SB6) is provided. From the graph, it is possible to easily determine the time when the blood vessel diameter is most expanded and the elastic modulus is lowered.
[0063]
Further, according to the above-described embodiment, the upstream end of both the first section and the second section is the heart, and the pulse wave propagation information measuring device 90 includes the electrocardiograph 34 that measures the electrocardiogram, and the heart Left pulse wave propagation time PCT using electrocardiogram signal SE detected by electrometer 34_LAnd right pulse wave propagation time PCT_RTherefore, the number of devices attached to the living body for measuring the pulse wave propagation time PCT is reduced.
[0064]
In the above-described embodiment, the left pulse wave propagation time PCT based on the electrocardiogram_LAnd right pulse wave propagation time PCT_RAnd the propagation time difference calculation means 92 (SB6) calculates the propagation time difference ΔPCT between the left pulse wave propagation time PCTL and the right pulse wave propagation time PCTR, so the left pulse wave propagation time PCTL and the right pulse wave propagation The precursor time included in the time PCTR is offset, and the propagation time difference ΔPCT is not affected by the precursor time. Therefore, the vascular endothelial function can be examined with high accuracy.
[0065]
Further, in the above-described embodiment, the blood driving device 82 performs blood driving with the upper arm portion, and the first section is a section from the heart to the wrist 52 on the side driven by the blood driving device 82. The first section includes a relatively long section downstream from the blood transfusion site. That is, since the first section includes a relatively long section in which the blood vessel dilates due to the cancellation of the blood pumping, the left pulse wave propagation time PCT_LThe amount of change after the cancellation of the tourniquet is relatively large. Accordingly, the propagation time difference ΔPCT calculated by the propagation time difference calculating means 92 (SB6) also increases after the release of the blood transfusion with respect to before the blood transfusion, so that the reliability of the examination of the vascular endothelial function becomes higher.
[0066]
Next, a second embodiment of the present invention will be described. In the description of the second embodiment, parts having the same configuration as that of the first embodiment are denoted by the same reference numerals and description thereof is omitted.
[0067]
The second embodiment is different from the first embodiment only in that the propagation time ratio R (PCT) is calculated instead of the propagation time difference ΔPCT of the first embodiment. Hereinafter, the difference will be described.
[0068]
FIG. 13 is a functional block diagram for explaining a main part of the control function of the CPU 68 in the vascular endothelial function testing device of the second embodiment. The propagation time ratio calculation means 96 functioning as the propagation information ratio calculation means is the left pulse wave propagation time PCT calculated for each beat by the pulse wave propagation time calculation means 88._LThe right pulse wave propagation time PCT_RBy dividing by, the propagation time ratio R (PCT), which is the ratio of the propagation time PCT based on the same beat, is calculated for each beat, and the time variation of the propagation time ratio R (PCT) calculated for each beat is calculated. Is displayed on the display 74 as a graph.
[0069]
FIG. 14 shows the left pulse wave propagation time PCT shown in FIGS._LAnd right pulse wave propagation time PCT_RFIG. 9 is a graph showing the time-dependent change in the propagation time ratio R (PCT) calculated from FIG. 7, (a) is FIG. 7, (b) is FIG. 8, (c) is FIG. 9, and (d) is the left pulse in FIG. Wave propagation time PCT_LAnd right pulse wave propagation time PCT_RIs the time-dependent change of the propagation time ratio R (PCT) calculated from As can be seen by comparing the graph shown in FIG. 14 with the lower graphs of FIGS. 7 to 10, the propagation time ratio R (PCT) shows substantially the same change as the propagation time difference ΔPCT.
[0070]
Returning to FIG. 13, the vascular endothelial function decrease determining means 98 differs from the vascular endothelial function decrease determining means 94 only in using the propagation time ratio R (PCT) instead of the propagation time difference ΔPCT. In other words, the vascular endothelial function lowering determining means 98 determines a peak value from the propagation time ratio R (PCT) after the cancellation of the blood transfusion calculated by the propagation time ratio calculating means 96, and the propagation before the start of the blood transfusion from the peak value. By subtracting the time ratio R (PCT), calculate the difference between before and after propagation of the propagation time ratio R (PCT), or the peak value is the propagation time ratio R (PCT) By dividing, the ratio before and after the blood transfusion of the propagation time ratio R (PCT) is calculated. When the front-rear difference or front-rear ratio is equal to or less than a criterion value set in advance based on experiments, it is determined that the vascular endothelial function is deteriorated, and characters or symbols indicating that are displayed on the display 74. To display.
[0071]
According to the second embodiment described above, the propagation time ratio R (PCT) calculated by the propagation time ratio calculating means 96 is equal to the left pulse wave propagation time PCT in the sections substantially in contrast to the median plane._LAnd right pulse wave propagation time PCT_RTherefore, the propagation time ratio R (PCT) is not affected by fluctuations in blood pressure, heart rate, and other systemic factors for each beat, and changes after the release of the hemostasis compared to before Become clear. Therefore, if the vascular endothelial function is examined based on the propagation time ratio R (PCT), the vascular endothelial function can be examined with high reliability. Further, as described above, the measurement of the pulse wave propagation time PCT has the advantage that it does not require skill and the apparatus is inexpensive. Further, the decrease in vascular endothelial function is automatically determined by the vascular endothelial function decrease determining means 98.
[0072]
As mentioned above, although embodiment of this invention was described in detail based on drawing, this invention is applied also in another aspect.
[0073]
For example, in the above-described embodiment, the pulse wave propagation time PCT is calculated as the pulse wave propagation information, but the pulse wave propagation speed PWV may be calculated instead of the pulse wave propagation time PCT.
[0074]
In the above-described embodiment, the upper arm portion is used for blood drive by the blood drive device 82, but the forearm portion, the wrist, the thigh, the lower leg, and the ankle may be used. When the thigh, lower leg, and ankles are used to drive blood, the first section is, for example, the upstream end is the heart, neck, upper arm, etc., and the downstream end is the side of the side to be driven. The ankles and fingertips of the feet. Further, when the upper arm portion is used for driving as in the above-described embodiment, the first section is not limited to the above-described embodiment. For example, the upstream end may be a neck portion or an upper arm portion. The downstream end may be the fingertip of the hand.
[0075]
In the above-described embodiment, the electrocardiograph that detects the electrocardiogram signal SE as the heartbeat synchronization signal is used as the heartbeat synchronization signal detection device. However, the heartbeat microphone that measures the heart sound signal (heart sound diagram) is detected by the heartbeat synchronization signal. It may be used as a device.
[0076]
In the first embodiment described above, the propagation time difference ΔPCT is equal to the left pulse wave propagation time PCT._LTo right pulse wave propagation time PCT_RWas calculated by subtracting the right pulse wave propagation time PCT_RTo left pulse wave propagation time PCT_LThe propagation time difference ΔPCT may be calculated by subtracting. Similarly, in the second embodiment, the right pulse wave propagation time PCT_RThe left pulse wave propagation time PCT_LThe propagation time ratio R (PCT) may be calculated by dividing by.
[0077]
Further, in the above-described embodiment, the difference between before and after is the propagation time difference ΔPCT (or propagation time ratio R (PCT)) before the start of blood transduction from the peak of the propagation time difference ΔPCT (or propagation time ratio R (PCT)) after the cancellation of the blood transfusion. ), But the peak of the propagation time difference ΔPCT (or propagation time ratio R (PCT)) before the start of blood transfusion to the propagation time difference ΔPCT (or propagation time ratio R (PCT)) after the blood transfusion is released The difference between before and after may be calculated by subtracting.
[0078]
In the above-described embodiment, the display 74 is used as an output device. However, the output device may be a printer.
[0079]
The present invention can be modified in various ways without departing from the gist thereof.
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating a configuration of a vascular endothelial function testing device to which the present invention is applied.
2 is a view showing a state in which a cuff and a pressure pulse wave detection probe provided in the vascular endothelial function testing device of FIG. 1 are attached to a patient. FIG.
3 is a diagram showing in detail the configuration of the pressure pulse wave detection probe of FIG. 1. FIG.
4 is a view showing a pressing surface of a pressure pulse wave sensor provided in the pressure pulse wave detection probe of FIG. 3; FIG.
FIG. 5 is a functional block diagram illustrating a main part of a control function of a CPU in the vascular endothelial function testing device of FIG. 1;
6 is a diagram for explaining an optimum pressing force HDPO determined by the pressing force control means in FIG. 5. FIG.
7 is a diagram showing the right pulse wave propagation time, the left pulse wave propagation time, and the propagation time difference calculated by the pulse wave propagation time calculation unit and the propagation time difference calculation unit of FIG. 5 side by side. FIG.
8 is a diagram showing the right pulse wave propagation time, the left pulse wave propagation time, and the propagation time difference calculated by the pulse wave propagation time calculation unit and the propagation time difference calculation unit of FIG.
9 is a diagram showing the right pulse wave propagation time, the left pulse wave propagation time, and the propagation time difference calculated by the pulse wave propagation time calculation unit and the propagation time difference calculation unit of FIG. 5 side by side.
10 is a diagram side by side showing a right pulse wave propagation time, a left pulse wave propagation time, and a propagation time difference calculated by the pulse wave propagation time calculation unit and the propagation time difference calculation unit of FIG. 5;
11 is a flowchart showing a main part of the control operation of the CPU shown in the functional block diagram of FIG. 5, and shows a signal collection routine.
12 is a flowchart showing a main part of the control operation of the CPU shown in the functional block diagram of FIG. 5, and shows a signal calculation routine.
FIG. 13 is a functional block diagram illustrating a main part of a control function of a CPU in the vascular endothelial function testing device according to the second embodiment of the present invention.
14 is a left pulse wave propagation time PCT shown in FIGS. 7 to 10. FIG._LAnd right pulse wave propagation time PCT_RFIG. 6 is a diagram showing a change with time of a propagation time ratio R (PCT) calculated from
[Explanation of symbols]
10: Vascular endothelial function testing device
34: electrocardiograph (heart rate synchronization signal detection device)
74: Display (output device)
82: Blood drive device
88: Pulse wave propagation time calculation means (pulse wave propagation information calculation means)
90: Pulse wave propagation information measuring device
92: Propagation time difference calculation means (propagation information difference calculation means)
94: Vascular endothelial function decrease judging means
96: Propagation time ratio calculation means (propagation information ratio calculation means)
98: Means for determining decrease in vascular endothelial function

Claims (9)

A blood-feeding device for driving arteries of a predetermined part of a living body for a predetermined time or more set in advance;
The first pulse wave propagation information, which is pulse wave propagation information related to the speed of propagation of the pulse wave in the artery of the first section including the site downstream of the blood pumping site by the blood feeding device, and the median plane A pulse wave propagation information measuring device that sequentially measures second pulse wave propagation information that is the pulse wave propagation information of the artery of the second section that is substantially symmetrical to the first section;
Propagation information difference calculation for calculating the propagation information difference between the first pulse wave propagation information and the second pulse wave propagation information before and after the blood transfusion is released by the blood transducing device. A vascular endothelial function testing device. The absolute value of the front-to-back difference, which is the difference between the propagation information difference after cancellation of blood transfusion calculated by the propagation information difference calculation means and the transmission information difference before blood transmission, is equal to or less than a predetermined criterion value. The vascular endothelial function test apparatus according to claim 1, further comprising a vascular endothelial function lowering determination means for determining a decrease in vascular endothelial function based on the above. The vascular endothelial function testing device according to claim 1, further comprising an output device that displays a graph of a temporal change in the propagation information difference calculated by the propagation information difference calculation means. A blood-feeding device for driving arteries of a predetermined part of a living body for a predetermined time or more set in advance;
The first pulse wave propagation information, which is pulse wave propagation information related to the speed of propagation of the pulse wave in the artery of the first section including the site downstream of the blood pumping site by the blood feeding device, and the median plane A pulse wave propagation information measuring device that sequentially measures second pulse wave propagation information that is the pulse wave propagation information of the artery of the second section that is substantially symmetrical to the first section;
Propagation information ratio calculation for calculating a propagation information ratio between the first pulse wave propagation information and the second pulse wave propagation information before and after the blood transfusion device releases the blood transfusion. A vascular endothelial function testing device. The absolute value of the front-back difference, which is the difference between the peak in the propagation information ratio after cancellation of blood transfusion calculated by the propagation information ratio calculation means and the transmission information ratio before blood transmission is less than or equal to a preset criterion value. 5. The vascular endothelial function test apparatus according to claim 4, further comprising a vascular endothelial function decrease determining means for determining a decrease in vascular endothelial function based on the above. 6. The vascular endothelial function testing device according to claim 4 or 5, further comprising an output device that graphically displays a change with time of the propagation information ratio calculated by the propagation information ratio calculation means. The vascular endothelial function testing device according to any one of claims 1 to 6,
The first section and the second section are both upstream at the heart,
The pulse wave propagation information measuring device includes a heartbeat synchronization signal detection device that detects a heartbeat synchronization signal generated from the heart of the living body, and the first pulse is detected using the heartbeat synchronization signal detected by the heartbeat synchronization signal detection device. An apparatus for examining vascular endothelial function, which measures wave propagation information and the second pulse wave propagation information, respectively. The vascular endothelial function testing device according to claim 7,
The heartbeat synchronization signal detection device is an electrocardiograph that measures the action potential of the myocardium,
Both of the first pulse wave propagation information and the second pulse wave propagation information are pulse wave propagation times. The blood driving device is for driving blood in the upper arm of the living body,
9. The vascular endothelial function testing device according to claim 1, wherein the first section is a section from a heart to a wrist on the side driven by the blood driving device.

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