JP3976279B1 - Vascular function testing device and program - Google Patents

Abstract

A blood vessel function is more accurately examined by improving the measurement accuracy of an index of arteriosclerosis such as PWV.
When baPWV (upper arm-ankle pulse wave velocity) is used as an index of vascular stiffness, the relationship of baPWV to the sympathetic nerve activity index (LF / HF) is approximated to a linear function and displayed. . The displayed graph indicates that the value of baPWV when the subject is at rest (cool) is 19.8 m / sec (intercept), and the slope of baPWV with respect to LF / HF of the subject is 0. .52. By using this graph, the influence of the state of the autonomic nerve can be excluded from the measured baPWV value, so that the blood vessel function can be examined with higher accuracy.
[Selection] Figure 7

Description

  The present invention relates to a blood vessel function testing device for testing a blood vessel function using a degree of blood vessel hardening that is an index indicating the hardness of a blood vessel.

  In recent years, arteriosclerosis is increasing due to changes in eating habits, unexpected movements, aging, and the like. In order to prevent such arteriosclerosis, it is necessary to diagnose how much arteriosclerosis is progressing. As a method for diagnosing the degree of arteriosclerosis, a method of measuring the degree of arterial stiffness using a pulse wave velocity (hereinafter abbreviated as PWV (Pulse Wave Velocity)) is known. The PWV is a speed at which a pulse wave generated when the heart ejects blood propagates through the blood vessel wall.

  A blood vessel in which arteriosclerosis has progressed is hard, so the PWV is fast, and a blood vessel in which arteriosclerosis has not progressed is very flexible, so the PWV is slow. Therefore, it is possible to diagnose the degree of progression of arteriosclerosis by measuring the measurement subject's PWV.

  However, since the PWV value has a problem that it depends on blood pressure, a method of measuring the degree of vascular sclerosis with high accuracy by removing the influence of blood pressure has been proposed (for example, Patent Document 1, 2 and 3). In the methods disclosed in Patent Documents 1, 2, and 3, the degree of vascular sclerosis excluding the dependency due to blood pressure is diagnosed by using CAVI (Cardio Ankle Vascular Index) as an index indicating the degree of arteriosclerosis. .

  However, even if an attempt is made to examine the state of arteriosclerosis using such an index such as PWV or CAVI, the measured value varies depending on the condition of the subject, and thus the blood vessel function cannot be examined with high accuracy. There was a case.

JP 2006-6893 A JP 2006-110155 A JP 2006-280784 A

  The conventional inspection method described above has a problem in that the measurement value varies depending on the condition of the person being measured, and the blood vessel function may not be accurately inspected.

  The objective of this invention is providing the vascular function test | inspection apparatus which can test | inspect a vascular function more accurately.

[Vessel function testing device]
In order to achieve the above object, the vascular function testing device of the present invention comprises an electrocardiogram measuring means for measuring the electrocardiogram of a living body,
Autonomic nerve activity calculating means for calculating a sympathetic nerve activity index indicating the degree of sympathetic nerve activity based on the electrocardiographic data measured by the electrocardiogram measuring means;
A vascular sclerosis measuring means for measuring vascular sclerosis that is an index indicating the hardness of a blood vessel of a living body;
The sympathetic nerve activity index is calculated based on the sympathetic nerve activity index of the same living body calculated by the autonomic nerve activity calculating means and the vascular sclerosis degrees of the same living body measured by the vascular sclerosis measuring means. A calculation means for calculating the relationship of the degree of vascular sclerosis;
Output means for outputting the result calculated by the calculating means.

  According to the present invention, since the calculation result of calculating the relationship between the degree of vascular sclerosis and the sympathetic nerve activity index is displayed, the influence of the state of the autonomic nerve can be removed from the index indicating the hardness of the blood vessel of the living body. The function can be inspected with higher accuracy.

In addition, the blood vessel function test apparatus of the present invention includes an accepting means for accepting electrocardiographic data measured by the electrocardiogram measuring means,
Autonomic nerve activity degree calculating means for calculating a sympathetic nerve activity index indicating the degree of sympathetic nerve activity based on the electrocardiogram data received by the receiving means;
A vascular sclerosis measuring means for measuring vascular sclerosis that is an index indicating the hardness of a blood vessel of a living body;
The sympathetic nerve activity index is calculated based on the sympathetic nerve activity index of the same living body calculated by the autonomic nerve activity calculating means and the vascular sclerosis degrees of the same living body measured by the vascular sclerosis measuring means. A calculation means for calculating the relationship of the degree of vascular sclerosis;
Output means for outputting the result calculated by the calculating means.

Preferably, the vascular sclerosis degree measuring means is
A pulse wave detecting means for detecting pulse waves at at least two parts of the living body;
A heart sound detecting means for detecting a heart sound of a living body;
And a calculation means for calculating the pulse wave velocity based on the pulse wave detected by the pulse wave detection means and the heart sound detected by the heart sound detection means.

  Preferably, the vascular sclerosis degree measuring means further includes a blood pressure measurement means for measuring blood pressure of the living body, and measures the vascular sclerosis degree using the blood pressure measurement means.

  Preferably, the calculation means approximates the relationship between the vascular sclerosis degree and the sympathetic nerve activity index to a linear function.

[program]
The program of the present invention includes a step of measuring the electrocardiogram of a living body,
Calculating a sympathetic nerve activity index indicating the degree of sympathetic nerve activity based on the measured electrocardiographic data;
Measuring a degree of vascular sclerosis, which is an index indicating the hardness of a blood vessel in a living body;
Calculating a relationship between vascular stiffness degree for sympathetic activity indicator based on a plurality of the sympathetic activity indicator of the calculated the same living body and a plurality of vascular stiffness of the measured same organism,
Outputting a relationship of the degree of vascular sclerosis to the calculated sympathetic nerve activity index.

  As described above, according to the present invention, since the influence of the state of the autonomic nerve can be removed from the index indicating the hardness of the blood vessel of the living body, the blood vessel function can be examined with higher accuracy. An effect can be obtained.

  The inventor of the present application considered that the value of an index (degree of vascular sclerosis) indicating the hardness of a blood vessel such as CAVI or PWV might be influenced by the state of the autonomic nerve. In other words, when the sympathetic nerve was superior to the parasympathetic nerve, it was speculated that not only the blood pressure increased but also the blood vessels contracted by acting on the vascular smooth muscle. For this reason, the inventor of the present application considered that an index indicating the hardness of the original blood vessel can be obtained by removing the influence of the autonomic nerve from the index indicating the hardness of the blood vessel such as CAVI or PWV.

  In the following embodiment, a case where ba (brachial ankle) PWV is used as an index indicating the degree of hardening of blood vessels will be described. However, the present invention is not limited to such a case, and other than baPWV. It is possible to apply in the same manner as long as it is an index indicating the hardness of a blood vessel such as PWV and CAVI. Note that baPWV (upper arm-ankle joint PWV) indicates PWV obtained from a pulse wave waveform at the upper arm and ankle regions.

  Next, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a blood vessel function testing device according to an embodiment of the present invention.

  As shown in FIG. 1, the blood vessel function testing apparatus according to the present embodiment includes pulse wave detection sensors 8 and 9, a heart sound detection sensor 10 disposed in the vicinity of the heart, a heart sound measurement unit 12, and a pulse wave measurement unit. 13, an electrocardiogram monitor 14, a control device 18, a storage device 20, a display device 22 for displaying biological information, and an autonomic nerve activity degree calculation unit 24.

  The electrocardiogram monitor 14 attaches a minus electrode, for example, to the measurement subject's throat, a plus electrode on the left flank, and a body ground on the right flank, obtains heart movement as an electrical signal and records it as electrocardiographic data.

  The autonomic nerve activity calculating unit 24 calculates a parasympathetic nerve activity index (LF / HF) indicating the degree of sympathetic nerve activity based on the electrocardiographic data measured by the electrocardiogram monitor 14. A specific method for calculating LF and LF / HF will be described later. In the present embodiment, the autonomic nerve activity calculation unit 24 is described as a component independent of the control device 18, but the autonomic nerve activity calculation unit 24 may be included in the control device 18. .

  The heart sound measurement unit 12 outputs the heart sound data detected by the heart sound detection sensor 10 to the control device 18. In addition, the heart sound detection sensor 10 may be configured to be provided on the clavicle, the jawbone, or the like to detect the heart sound by bone transmission or the like.

  The pulse wave detection sensor 8 is provided on the upper arm of the measurement subject and measures the pulse wave of the upper arm. The pulse wave detection sensor 9 is provided on the ankle of the measurement subject and measures the pulse wave of the ankle. In the present embodiment, the case where a pressure detection sensor is used as the pulse wave detection sensors 8 and 9 has been described, but it is also possible to detect a pulse wave by using a cuff and using a cuff pressure. The pulse wave measurement unit 13 outputs the pulse wave signal measured by the pulse wave detection sensors 8 and 9 to the control device 18. In order to detect the pulse wave velocity, at least two pulse wave detection sensors are required.

  The control device 18 is composed of, for example, a computer, processes the biological information obtained by the heart sound measurement unit 12, the pulse wave measurement unit 13, and the autonomic nerve activity calculation unit 24, stores the processed information in the storage device 20, and Alternatively, it is displayed on the display device 22.

  In addition, the control device 18 includes receiving means for receiving the heart sound data of the measured person measured by the heart sound measuring unit 12, the pulse wave data of the measured person measured by the pulse wave measuring unit 13, and the electrocardiographic data. And a calculation means for calculating a pulse wave velocity based on the received heart sound data and pulse wave data.

  The calculation means and the pulse wave measurement unit 13, the pulse wave detection sensors 8 and 9, the heart sound measurement unit 12, and the heart sound detection sensor 10 measure the degree of vascular stiffness, which is an index indicating the hardness of the blood vessel of the measurement subject. A blood vessel sclerosis measuring means is configured.

  Further, the control device 18 calculates the relationship of the vascular stiffness to LF / HF based on the vascular stiffness measured by the vascular stiffness measuring means and the LF / HF calculated by the autonomic nerve activity calculator 24. Calculation means for The display device 22 functions as an output unit that outputs the result calculated by the calculation unit.

  Next, the operation of the blood vessel function testing device of this embodiment will be described with reference to FIG.

  First, the heart sound and pulse wave of the living body are measured by the heart sound measuring unit 12 and the pulse wave measuring unit 13, and the electrocardiogram data is measured by the electrocardiogram monitor 14 (S201). Then, the control device 18 calculates baPWV as an index of the degree of vascular stiffness based on the heart sound data measured by the heart sound measuring unit 12 and the pulse wave data measured by the pulse wave measuring unit 13 (S202). A specific calculation method of baPWV will be described later.

Next, the autonomic nerve activity calculation unit 24 performs LF / HF calculation based on the electrocardiogram data measured by the electrocardiogram monitor 14 to indicate a sympathetic nerve activity index (LF / HF) indicating the degree of sympathetic activity. Is calculated (S203). Note that the calculated baPWV value and the calculation result calculated by the autonomic nerve activity calculation unit 24 are stored in the storage device 20 by the control device 18. Then, the measurement shown in S201 to S203 is repeated a predetermined number of times (S204).
Next, the control device 18 calculates the relationship of baPWV to LF / HF by approximating the values of LF / HF and baPWV to a linear function (S205), and displays the calculation result on the display device 22 (S206). ).

  Next, the calculation method of baPWV shown in step S202 of FIG. 2 will be described with reference to FIG.

First, a heart sound is detected from the heart sound sensor 22. The heart sound is detected because it is difficult to read the heart sound valve opening sound that should originally be the starting point. Next, based on the pulse wave from the pulse wave detection sensor 8, a time difference tb between the heart sound and the notch of the pulse wave is detected. This time difference tb corresponds to the time from when the heart sound valve is opened to when the brachial pulse wave rises. Next, the rise of the pulse wave from the pulse wave detection sensor 9 is detected, and a time difference tba between the rise of the brachial pulse wave and the rise of the ankle pulse wave is detected. Therefore, the time from when the heart sound valve opens to the rise of the knee pulse wave is tb + tba. For this reason, baPWV is calculated as in the following equation (1).
baPWV = L / (tb + tba) (1)

  The notch is not directly detected from the ankle pulse wave because the ankle pulse wave is difficult to read.

  Next, details of the LF / HF calculation method shown in step S203 of FIG. 2 are shown in FIGS.

  FIG. 4 is a flowchart for explaining the LF / HF calculation method in the vascular function testing device of this embodiment. First, in step S <b> 401, the autonomic nerve activity calculation unit 24 calculates heart rate variability from the electrocardiographic data input from the electrocardiogram monitor 14. As shown in FIGS. 5A and 5B, the heart rate variability was calculated by measuring the RR interval by taking an interval between the R wave and the next R wave, and then measuring as shown in FIGS. 5C and D. The RR interval data is plotted at the time position of the backward R wave, interpolated, and then resampled at equal intervals (dotted line in FIG. 5C). In the next step S402, spectrum analysis (frequency conversion) is performed on the data obtained in step S401. An example of the spectrum analysis in step S402 is shown in FIG. In the next step S403, a low frequency component LF is obtained. Here, the low frequency component LF is an integral value of the power spectrum component of 0.04 to 0.15 Hz. In the next step S404, a high frequency component HF is obtained. Here, the high frequency component HF is an integral value of the power spectrum component of 0.15 to 0.40 Hz. In step S405, the ratio obtained in step S403 and the ratio obtained in step S404 are calculated to obtain LF / HF.

  In this manner, the autonomic nerve activity calculation unit 24 calculates the sympathetic nerve activity index (LF / HF) from the electrocardiogram data measured by the electrocardiogram monitor 14.

Next, FIG. 7 shows an example of display on the display device 22 in the blood vessel function testing device of the present embodiment.
FIG. 7 is a display example (graph) in which the display device 22 displays the result approximated by the control device 18 in step S206 shown in FIG.

As shown in FIG. 7, the approximate result displayed on the display device 22 is approximated from, for example, five measurement results of LF / HF and baPWV, and the following linear function indicating the relationship of baPWV to LF / HF: It has become.
Y = 0.52X + 19.8

  That is, the display device 22 indicates that the value of baPWV when the subject is at rest (cool) is 19.8 m / sec (intercept), and the slope of baPWV with respect to the LF / HF of the subject. Is shown to be 0.52.

  Therefore, according to the vascular function testing device of the present embodiment, it is possible to display the slope of the value of baPWV with respect to LF / HF for each measured person, regardless of the state of the measured person's autonomic nerve. , BaPWV can be measured accurately.

  Further, according to the vascular function testing device of the present embodiment, the influence of the autonomic state can be removed from the value of baPWV, so that the vascular function can be tested with higher accuracy. For example, if baPWV having a constant LF / HF value is always used as the measurement result to evaluate the vascular function, the vascular function can be evaluated without being affected by the state of the subject's autonomic nerve. .

[Modification]
In the above embodiment, the sympathetic nerve activity index LF / HF is used as the autonomic nerve function measuring means for measuring the autonomic nerve function. However, the present invention is not limited to this. For example, the parasympathetic nerve activity index HF is used. It may be used.

  Moreover, in the said embodiment, although baPWV was used as a blood-vessel hardening degree, you may make it use CAVI as a blood-vessel hardening degree. In this case, the CAVI may be calculated based on the pulse wave velocity and the blood pressure value by measuring the blood pressure of the measurement subject using the blood pressure measurement device. As a specific calculation method of CAVI, a method disclosed in Japanese Patent Application Laid-Open No. 2006-110155 or the like can be used, and a description of the specific calculation method is omitted here.

It is a block diagram which shows the structure of the blood vessel function test | inspection apparatus of one Embodiment of this invention. It is a flowchart which shows operation | movement of the vascular function test | inspection apparatus of one Embodiment of this invention. It is a figure for demonstrating the calculation method of baPWV in the blood vessel function test | inspection apparatus of one Embodiment of this invention. It is a flowchart for demonstrating the LF / HF calculation method in the blood vessel function test | inspection apparatus of one Embodiment of this invention. It is a figure which shows the heart rate fluctuation | variation measuring method in the case of LF / HF calculation. It is a figure which shows an example which spectrum-analyzed in the case of LF / HF calculation. It is a figure which shows an example of the display shown by the display apparatus 22 in FIG.

Explanation of symbols

8, 9 Pulse wave detection sensor 10 Heart sound detection sensor 12 Heart sound measurement unit 13 Pulse wave measurement unit 14 ECG monitor 18 Control device 20 Storage device 22 Display device 24 Autonomic nerve activity calculation unit S201 to S206 Steps S401 to S405 Steps

Claims (10)

An electrocardiogram measuring means for measuring the electrocardiogram of a living body;
Autonomic nerve activity calculating means for calculating a sympathetic nerve activity index indicating the degree of sympathetic nerve activity based on the electrocardiographic data measured by the electrocardiogram measuring means;
A vascular sclerosis measuring means for measuring vascular sclerosis that is an index indicating the hardness of a blood vessel of a living body;
The sympathetic nerve activity index is calculated based on the sympathetic nerve activity index of the same living body calculated by the autonomic nerve activity calculating means and the vascular sclerosis degrees of the same living body measured by the vascular sclerosis measuring means. A calculation means for calculating the relationship of the degree of vascular sclerosis;
Output means for outputting the result calculated by the calculating means;
A vascular function testing device having Receiving means for receiving electrocardiogram data measured by the electrocardiogram measuring means;
Autonomic nerve activity degree calculating means for calculating a sympathetic nerve activity index indicating the degree of sympathetic nerve activity based on the electrocardiogram data received by the receiving means;
A vascular sclerosis measuring means for measuring vascular sclerosis that is an index indicating the hardness of a blood vessel of a living body;
The sympathetic nerve activity index is calculated based on the sympathetic nerve activity index of the same living body calculated by the autonomic nerve activity calculating means and the vascular sclerosis degrees of the same living body measured by the vascular sclerosis measuring means. A calculation means for calculating the relationship of the degree of vascular sclerosis;
Output means for outputting the result calculated by the calculating means;
A vascular function testing device having The vascular sclerosis measuring means comprises:
A pulse wave detecting means for detecting pulse waves at at least two parts of the living body;
A heart sound detecting means for detecting a heart sound of a living body;
A computing means for computing a pulse wave velocity based on the pulse wave detected by the pulse wave detecting means and the heart sound detected by the heart sound detecting means;
The vascular function testing device according to claim 1 or 2, comprising:   The vascular function testing device according to claim 3, wherein the vascular sclerosis measuring means further includes a blood pressure measuring means for measuring blood pressure of a living body, and measures the vascular sclerosis degree using the blood pressure measuring means.   The vascular function testing device according to any one of claims 1 to 4, wherein the calculating means approximates a relationship between a vascular sclerosis degree and a sympathetic nerve activity index to a linear function. Measuring the electrocardiogram of the living body;
Calculating a sympathetic nerve activity index indicating the degree of sympathetic nerve activity based on the measured electrocardiographic data;
Measuring a degree of vascular sclerosis, which is an index indicating the hardness of a blood vessel in a living body;
Calculating a relationship between vascular stiffness degree for sympathetic activity indicator based on a plurality of the sympathetic activity indicator of the calculated the same living body and a plurality of vascular stiffness of the measured same organism,
Outputting a relationship between the degree of vascular sclerosis and the calculated sympathetic nerve activity index;
A program that causes a computer to execute. Receiving the electrocardiogram data measured by the electrocardiograph means;
Calculating a sympathetic nerve activity index indicating a degree of sympathetic nerve activity based on the received electrocardiogram data;
Measuring a degree of vascular sclerosis, which is an index indicating the hardness of a blood vessel in a living body;
Calculating a relationship between vascular stiffness degree for sympathetic activity indicator based on a plurality of the sympathetic activity indicator of the calculated the same living body and a plurality of vascular stiffness of the measured same organism,
Outputting a relationship between the degree of vascular sclerosis and the calculated sympathetic nerve activity index;
A program that causes a computer to execute. In the step of measuring the degree of vascular sclerosis,
Detecting pulse waves in at least two parts of the living body;
Detecting living body heart sounds;
The program according to claim 6 or 7, which causes the computer to execute a step of calculating a pulse wave velocity based on the detected pulse wave and the detected heart sound.   The program according to claim 8, wherein the step of measuring the degree of vascular sclerosis further includes the step of measuring blood pressure of the living body, and measures the degree of vascular sclerosis using the measured blood pressure value.   The program according to any one of claims 6 to 9, wherein the step of calculating the relationship between the sympathetic nerve activity index and the vascular sclerosis degree approximates the relationship between the sympathetic nerve activity index and the vascular sclerosis degree to a linear function.

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