JP2016144565A - Pulse wave measurement device and living body information measurement device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pulse wave measurement device capable of measuring a pulse wave which is desirable for PWV measurement.SOLUTION: Exciting coils 11, 12 and electrodes 21, 22 are provided in the surrounding of an aorta, the exciting coils generate a magnetic field passing through the aorta, and the electrodes 21, 22 are used to detect induction voltage which is generated by blood flowing through the aorta at that time, thereby detecting a pulse wave of the aorta. Therefore, the pulse wave of the aorta can be accurately detected in a non-invasive manner. Therefore, it becomes possible to accurately detect a timing when an aortic valve opens, and blood is actually driven out of the heart. Therefore, accurate PWV can be detected by measuring PWV using the drive timing.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a pulse wave measurement device and a biological information measurement device.

  In recent years, with the increasing aging society, early diagnosis and treatment of early treatment of arteriosclerotic diseases are urgently needed. As one method for quantitatively diagnosing arteriosclerosis in a non-invasive manner, an aortic pulse wave velocity test method for measuring a pulse wave velocity (PWV) between two points of the aorta is known.

  The aortic pulse wave velocity inspection method uses the property that the pulse wave velocity is fast in a hard substance and slow in a soft substance. In the aortic pulse wave velocity inspection method, first, the time required for the pulse wave to propagate between two points of the aorta in the same direction as viewed from the heart is measured, and then the measured time and the distance between the two points (arterial length). ) To calculate the pulse wave velocity. From the fact that the healthy arterial wall is soft and rich and the arteriosclerotic blood vessel wall is hard and brittle, it is diagnosed that the higher the measured pulse wave velocity, the more the arteriosclerosis is progressing.

  The types of PWV include cfPWV (carotid-femoral PWV: carotid-femoral PWV) (for example, see Non-Patent Document 1) and baPWV (brachial-ankle PWV: upper arm-ankle PWV) (for example, non-patent literature). 2), hcPWV (heart-carotid PWV).

  Furthermore, as an index of the degree of arteriosclerosis using PWV, there is CAVI (Cardio-Ankle Vascular Index) (for example, see Non-Patent Document 3). CAVI measures blood pressure and pulse wave by wearing a cuff on the upper arm and ankle (or popliteal area), and measures heart sound by wearing a heart sound microphone on the sternum.

Yoshiaki Masuda, Hiroshi Kanai, “Fundamental and Clinical Arterial Pulse Waves”, Kyoritsu Shuppan, 15-19 pages, 2000 Toshio Ozawa, Yoshiaki Masuda, "Pulse wave velocity", Medical View, 28-29 pages Kohji Shirai, Junji Utino, Kuniaki Ohtsuka, Masanobu Takada, "A Novel Blood Pressure-independent Arterial Wall Stiffness Parameter; Cardio-Ankle Vascular Index (CAVI)", Journal of Atherosclerosis and Thrombosis, Vol.13, No.2

  By the way, in the conventional cfPWV, the starting point for measuring PWV is the carotid artery and the end point is the groin of the femoral artery, and in baPWV, the starting point is the upper arm and the end point is the ankle. In the PWV measurement, it is ideal to place the starting point on the upstream side and the end point on the downstream side as viewed from the blood flow (in other words, in the propagation direction of the pulse). However, both cfPWV and baPWV are not preferable because the starting point and the ending point are set on an artery where blood ejected from the heart branches in different directions. The reason why the starting point and the ending point have to be set at such positions is that the position where the arterial pulse wave can be taken is actually limited to the position where the artery is close to the body surface.

  In addition, hcPWV uses elements that are difficult to measure, such as heart sounds and notch portions of arteries, which may reduce accuracy.

  The present invention has been made in consideration of the above points, and a pulse wave measuring device capable of measuring a pulse wave preferable for PWV measurement, and obtaining biological information such as PWV with high accuracy using the pulse wave. Provided is a biological information measuring device capable of

One aspect of the pulse wave measuring device of the present invention is:
A pulse wave measuring device for non-invasively measuring a pulse wave,
A magnetic flux generator that generates magnetic flux toward the subject;
A pulse wave detector that detects an induced voltage generated by the magnetic flux generated from the magnetic flux generator and a blood flow of the subject, and detects a pulse wave based on the induced voltage;
It comprises.

One aspect of the pulse wave measuring device of the present invention is:
First and second excitation coils arranged at positions sandwiching the body of the subject;
First and second electrodes disposed at positions sandwiching the body portion;
A coil excitation amplification circuit for supplying an excitation current to the first and second excitation coils;
A pulse wave measuring unit for detecting a pulse wave of the aorta based on an induced voltage generated between the first and second electrodes;
It comprises.

One aspect of the biological information measuring device of the present invention is:
The pulse wave measuring device;
A peripheral arterial pulse wave measurement unit for measuring a peripheral arterial pulse wave of a subject far from the heart than a measurement point by the pulse wave measuring device;
The first timing at which blood is ejected from the heart is detected based on the aortic pulse wave obtained by the pulse wave measuring device, and the peripheral artery pulse wave is obtained based on the peripheral arterial pulse wave obtained by the peripheral arterial pulse wave measuring unit. A calculation unit that detects a second timing at which the pulse arrives at a site where the arterial pulse wave measurement unit is mounted, and calculates a pulse wave propagation time from a difference between the second timing and the first timing;
It comprises.

One aspect of the biological information measuring device of the present invention is:
The pulse wave measuring device;
A peripheral arterial pulse wave measurement unit for measuring a peripheral arterial pulse wave of a subject far from the heart than a measurement point by the pulse wave measuring device;
The first timing based on the pulse wave obtained by the pulse wave measurement device is detected, and the peripheral artery pulse wave measurement unit is mounted based on the peripheral artery pulse wave obtained by the peripheral artery pulse wave measurement unit. Calculating a pulse wave propagation time from a difference between the second timing and the first timing;
It comprises.

  According to the present invention, when blood is discharged from the heart to the artery and the blood flow volume in the artery increases, the induced voltage generated by the magnetic field generated from the magnetic flux generation unit and the blood flow of the subject also increases. The pulse wave detector can detect the arterial pulse wave based on the increase of the induced voltage. Therefore, the pulse wave of the artery located deep from the body surface can also be detected.

  According to the present invention, when blood is discharged from the heart to the aorta and the blood flow in the aorta increases, the voltage induced in the aorta by the magnetic fields generated from the first and second excitation coils also increases. Then, the induced voltage generated between the first and second electrodes also increases. The pulse wave measuring unit can detect the aortic pulse wave based on the increase of the induced voltage. Therefore, the pulse wave of the aorta in a deep part from the body surface can be detected.

  As a result, for example, the timing at which the aortic valve opens and blood is actually ejected from the heart can be detected noninvasively with high accuracy. Therefore, by obtaining the pulse wave velocity using the blood ejection timing from the heart, it is possible to obtain an accurate pulse wave velocity.

Schematic diagram showing the position of the excitation coil as seen from the side of the human body Schematic diagram showing the position of the excitation coil as seen from the front of the human body Schematic diagram showing the positions of electrodes as seen from the side of the human body Schematic diagram showing the positions of electrodes as seen from the front of the human body Schematic representation of the relationship between excitation coil, electrode and aorta The block diagram which shows the whole structure of the biological information measuring device which concerns on embodiment Flow chart showing the calculation procedure of pulse wave velocity using aortic pulse wave and pressure pulse wave Diagram for explaining the propagation time of pulse wave from aortic pulse wave and pressure pulse wave

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

<Principle>
First, the principle of the present invention will be described before describing the specific configuration of the embodiment.

  In the present invention, the principle of an electromagnetic blood flow meter or an electromagnetic flow meter is applied to a pulse wave measuring device so that a pulse wave can be measured noninvasively with high accuracy.

  In the present embodiment, a magnetic field is applied in a direction orthogonal to the aorta. Then, an induced voltage corresponding to the blood flow in the aorta is generated in a direction orthogonal to the aorta according to Faraday's law. That is, an electromotive voltage is generated at the moment when blood flows through the aorta, and in the present embodiment, this is detected by the electrodes. As a result, the opening time of the aortic valve can be detected.

  This will be described in more detail. When the heart contracts, the aortic valve opens and the ejected blood begins to flow rapidly into the aorta. Therefore, when a magnetic field is applied in a direction orthogonal to the aorta, an induced voltage is generated at the timing when blood begins to flow through the aorta. As a result, an induced voltage is detected by an electrode in a direction perpendicular to the aorta. Therefore, if at least two electrodes are provided in a direction orthogonal to the blood flow of the aorta and the induced voltage generated between the electrodes is measured, the aortic pulse wave can be measured.

  1 to 4 are diagrams showing a basic configuration of the present embodiment. 1 and 3 are views seen from the side of the human body, and FIGS. 2 and 4 are views seen from the front of the human body.

  As shown in FIGS. 1 and 2, in the present embodiment, a first excitation coil 11 is disposed on the front surface of a human body (subject) and a second excitation coil 12 is disposed on the rear surface. 11 and 12 are used to generate a magnetic field in a direction substantially perpendicular to the longitudinal direction of the aorta. The exciting coils 11 and 12 are arranged at a position where a magnetic field can be focused on the aorta. That is, the exciting coils 11 and 12 are arranged so that the magnetic flux density at the position of the aorta is increased. The excitation coils 11 and 12 are preferably configured to be Helmholtz coils. In this way, by arranging the exciting coils 11 and 12 so that the central axis that penetrates the exciting coils 11 and 12 penetrates the aorta (that is, the magnetic flux that penetrates the aorta is generated), A uniform magnetic field can be formed.

  In addition, as shown in FIGS. 3 and 4, first and second electrodes 21, 22 are arranged on both sides of the body, and the electrodes 21, 22 are generated by the current flowing through the aorta using the electrodes 21, 22. An induced voltage generated between them is detected. Here, the 1st and 2nd exciting coils 11 and 12 are arrange | positioned so that the magnetic force line which penetrates the trunk | drum to generate | occur | produce may be orthogonal to the longitudinal direction of an aorta. The first and second electrodes 21 and 22 are arranged so that a line connecting the first and second electrodes 21 and 22 is orthogonal to both the longitudinal direction of the aorta and the magnetic field lines. That is, the three directions of the longitudinal direction of the aorta, the direction passing through the body of the magnetic field lines, and the direction connecting the two electrodes are orthogonal to each other. By doing in this way, the induced voltage according to the blood flow which flows into the aorta can be obtained efficiently.

  The position where the magnetic field is focused by the exciting coils 11 and 12 is preferably the position of the descending aorta slightly below the position where the ascending aorta and the descending aorta overlap. This is because at the position where the ascending aorta and the descending aorta overlap, blood flows upward in the ascending aorta and blood flows downward in the descending aorta, so that the ascending aorta and the descending aorta are reversed by the magnetic field generated by the excitation coils 11 and 12. This is because an induced voltage in the direction is generated, and as a result, the induced voltage generated between the electrodes 21 and 22 may be canceled out. However, even at a position where the ascending aorta and the descending aorta overlap, if the magnetic field generated by the exciting coils 11 and 12 can be focused on either the ascending aorta or the descending aorta, the above-described cancellation of the induced voltage is eliminated.

  FIG. 5 is a diagram schematically showing the relationship between the exciting coils 11 and 12, the electrodes 21 and 22, and the aorta. When the magnetic field B generated by the excitation coils 11 and 12 penetrates blood, which is a conductive fluid in the aorta, an induced voltage is generated by the blood flow. A voltage e corresponding to the induced voltage is generated between the electrodes 21 and 22. Therefore, it is possible to detect the timing at which blood begins to flow into the aorta based on the induced voltage e.

  In addition, since the length from the position where the timing at which the blood begins to flow into the aorta by the exciting coils 11 and 12 and the electrodes 21 and 22 to the aortic root can be easily estimated from the height of the subject, the aorta The valve opening time (blood ejection timing) can be easily corrected.

  In the present invention, the excitation coils 11 and 12 and the electrodes 21 and 22 are used in this way to obtain the timing when blood begins to flow into the aorta, and then the opening time of the aortic valve (blood ejection timing) is detected. The pulse wave propagation time can be measured by measuring the pulse wave arrival time from this aortic valve opening point to another pulse wave detection site, and the PWV can be obtained using the pulse wave propagation time.

<Embodiment>
FIG. 6 is a schematic diagram showing the overall configuration of a biological information measuring device equipped with the pulse wave measuring device of the present invention.

  The biological information measuring apparatus 100 includes a first cuff 110 and a second cuff 120. A first electrode 111 and a second electrode 121 are provided on each of the first cuff 110 and the second cuff 120. The first cuff 110 is attached to the subject's upper limb, and the second cuff 120 is attached to the subject's lower limb. In the present embodiment, the first cuff 110 is attached to the left upper arm, and the second cuff 120 is attached to the right ankle.

  Furthermore, the biological information measuring apparatus 100 includes a blood pressure pulse wave measurement unit 130, a coil excitation amplification circuit unit 140, an induced voltage / pulse wave measurement unit 150, an electrocardiogram measurement unit 160, a control / calculation unit 170, a storage unit 181 and an input unit 182. , A display unit 183, an audio unit 184, and a printing unit 185.

  The control / arithmetic unit 170 includes a CPU (Central Processing Unit), a memory, and the like, and controls the operation of each unit in the apparatus by executing a biological information measurement program stored in the memory by the CPU. Perform operations necessary to obtain information.

  The storage unit 181 is a storage device such as a hard disk, and stores measurement results and the like under the control of the control / calculation unit 170. The input unit 182 includes an input device such as a keyboard, a mouse, or a button, and outputs an operation signal corresponding to a user operation to the control / calculation unit 170. The control / calculation unit 170 performs control and calculation according to the operation signal. The display unit 183 is a display device such as a liquid crystal display, and displays a setting screen, operation guidance, a biological information test result report, or the like under the control of the control / calculation unit 170. Note that the display unit 183 may be configured by a touch panel and may have an input function in addition to the display function. The voice unit 184 is a speaker device, and outputs operation guidance or an alarm sound according to the control of the control / calculation unit 170. The printing unit 185 is a printer device such as a thermal printer, and prints a biological information test result report or the like under the control of the control / calculation unit 170.

  The blood pressure pulse wave measurement unit 130 measures the pulse wave and blood pressure of the peripheral artery of the subject. The blood pressure pulse wave measurement unit 130 includes a pump and an exhaust valve for supplying and exhausting the cuffs 110 and 120, a pressure sensor for detecting the pressure of the cuffs 110 and 120, and a predetermined signal such as amplification for a detection signal from the pressure sensor. It comprises a signal processing circuit that performs the signal processing. The blood pressure pulse wave measurement unit 130 increases the internal pressure of the cuffs 110 and 120 (hereinafter, the internal pressure of the cuff is referred to as “cuff pressure”) by introducing air into the air bags of the cuffs 110 and 120 through the hose, The cuff pressure of the cuffs 110 and 120 is reduced by discharging air from the air bag. The target value of the cuff pressure after pressurization is different for pulse wave measurement and blood pressure measurement, and can be set individually.

  In the case of this embodiment, the measurement of the peripheral arterial pulse wave and the measurement of the aortic pulse wave are performed simultaneously.

  The peripheral arterial pulse wave can be measured using both the first cuff 110 and the second cuff 120, or either the first cuff 110 or the second cuff 120. In the case of the present embodiment, blood pressure is measured using the first cuff 110, that is, the upper arm cuff, and the peripheral arterial pulse wave is measured using the second cuff 120.

  When measuring the peripheral artery pulse wave, the blood pressure pulse wave measurement unit 130 first pressurizes the cuff 120 until the cuff pressure reaches a predetermined value. The blood pressure pulse wave measurement unit 130 detects a change in the cuff pressure of the cuff 120 after pressurization with a pressure sensor as a peripheral arterial pulse wave signal, and outputs the detected peripheral arterial pulse wave signal to the control / calculation unit 170.

  On the other hand, in the case of blood pressure measurement, the blood pressure pulse wave measurement unit 130 pressurizes the cuff 110 to a predetermined value that would stop the blood, and then detects vibrations of the cuff 110 during the decompression using the pressure sensor. The cuff pressure at the time when the amplitude starts to increase is detected as the systolic blood pressure, and the cuff pressure at which the vibration decrease is most significant is detected as the diastolic blood pressure. Then, the blood pressure pulse wave measurement unit 130 outputs blood pressure signals respectively indicating the detected systolic blood pressure and diastolic blood pressure to the control / calculation unit 170.

  The electrocardiogram measurement unit 160 is connected to electrodes 111 and 121 provided on the surfaces of the cuffs 110 and 120 that are in contact with the body surface. The electrocardiogram measurement unit 160 has a signal processing circuit that performs predetermined signal processing such as amplification on the detection signals detected by the electrodes 111 and 121. The electrocardiogram measurement unit 160 outputs the detection signal after the signal processing to the control / calculation unit 170 as an electrocardiogram signal.

  The coil excitation amplification circuit unit 140 supplies current to the excitation coils 11 and 12. In the case of the present embodiment, the frequency of the high-frequency current supplied by the coil excitation amplification circuit unit 140 is on the order of several kHz to 100 kHz. In the present embodiment, a high frequency current of about 50 kHz is supplied to the exciting coils 11 and 12. What is necessary is just to change suitably the electric current and frequency supplied to the exciting coils 11 and 12 according to the performance, arrangement position, etc. of an exciting coil.

  Here, the frequency of the high-frequency current supplied to the exciting coils 11 and 12 is on the order of several kHz to 100 kHz, while the electrocardiogram component is about 100 Hz at most, and the frequency band is greatly separated. Therefore, even if the electrocardiogram measurement and the high-frequency current are simultaneously performed, the electrocardiogram measurement is not adversely affected.

  The induced voltage / pulse wave measurement unit 150 obtains an aortic pulse wave signal based on the induced voltage generated between the electrodes 21 and 22. Specifically, the electrodes 21 and 22 are provided near the body surface of the subject, and when blood flows through the aorta, an induced voltage is generated according to Faraday's law. The induced voltage / pulse wave measuring unit 150 obtains an aortic pulse wave signal based on the induced voltage.

  As described above, the induced voltage generated when a magnetic field is applied to the path passing through the aorta by the exciting coils 11 and 12 varies depending on the blood flow volume of the aorta and increases as the blood flow volume increases. Therefore, immediately after the opening of the aortic valve, a pulsatile flow of the aorta occurs, the blood flow volume increases, and the induced voltage increases. The aortic pulse wave obtained by the induced voltage / pulse wave measuring unit 150 is a pulse wave that varies due to the pulsating flow from such an aortic valve. By observing the aortic pulse wave, the timing at which blood is ejected from the aortic valve can be detected. If the ejection timing of blood from the heart is detected using this aortic pulse wave, the ejection timing of blood from the heart can be detected with high accuracy because the blood flow is directly detected. On the other hand, in the method of detecting the ejection timing of blood from the heart by detecting the movement of the heart using a piezoelectric sensor or the like, the blood flows after the heart starts to move according to the presence or absence of heart disease or blood pressure. Since the time interval until ejection is different, it is difficult to accurately estimate the ejection timing of blood from the motion of the heart.

  Next, a method for calculating PWV using the aortic pulse wave and the peripheral arterial pulse wave will be described with reference to FIGS.

  In calculating PWV, the control / arithmetic unit 170 executes the processing procedure shown in FIG. When the control / calculation unit 170 starts the PWV calculation process in step S <b> 0, the control / calculation unit 170 sets the cuff pressures of the cuffs 110 and 120 to be pressurized by the blood pressure pulse wave measurement unit 130 in step S <b> 1. In step S2, the aortic pulse wave measured by the induced voltage / pulse wave measuring unit 150 is read, and in step S3, the peripheral artery pulse wave measured by the blood pressure pulse wave measuring unit 130 is read.

  The state of the aortic pulse wave and the peripheral arterial pulse wave read in steps S2 and S3 is shown in FIG. In FIG. 8, the time axes of the aortic pulse wave and the peripheral arterial pulse wave are shown in accordance with the same time axis.

  In step S4, the control / calculation unit 170 detects a change point (that is, a rising point) at which the aortic pulse wave increases and a change point (that is, a rising point) at which the pressure of the peripheral artery pulse wave increases. In detecting the change point, for example, a differential method or the like can be used. In the example of FIG. 8, the aortic pulse wave has the above-mentioned changing point at the time point t1, and the peripheral arterial pulse wave has the above-mentioned changing point at the time t2.

  In step S5, the control / calculation unit 170 calculates the pulse wave propagation time T from the heart to the attachment site of the second cuff 120 by calculating t2-t1. Next, in step S6, the controller / arithmetic unit 170 calculates P / VV by calculating T / L using a preset distance L from the heart to the attachment site of the second cuff 120.

  As described above, according to the present embodiment, the exciting coils 11 and 12 and the electrodes 21 and 22 are provided, and a magnetic field passing through the aorta is generated by the exciting coils 11 and 12, and then ejected from the aorta. The aortic pulse wave is detected by detecting the induced voltage induced by the blood to be detected using the electrodes 21 and 22. Thereby, the aortic pulse wave can be detected non-invasively and accurately. Therefore, the timing at which the aortic valve is opened and blood is actually ejected from the heart can be accurately detected. Therefore, the PWV can be detected with high accuracy by measuring the PWV using this ejection timing.

  The biological information measuring apparatus 100 according to the present embodiment includes the electrocardiogram measuring unit 160. Therefore, when the level of the aortic pulse wave measured by the induced voltage / pulse wave measuring unit 150 is small, the electrocardiogram is used as a reference. Then, it becomes possible to narrow down the time point at which the change point in the aortic pulse wave is to be detected (that is, to set the target range). Specifically, since it is known that the aortic pulse wave appears several tens of milliseconds after the R wave of the electrocardiogram, the aortic pulse wave may be detected in the vicinity thereof.

  In the above-described embodiment, the case where the exciting coils 11 and 12 are provided on the front and back surfaces of the human body and the electrodes 21 and 22 are provided on the side surfaces of the human body has been described, but the present invention is not limited thereto. In short, the excitation coils 11 and 12 need only be arranged at positions where magnetic flux passing through a desired position of the aorta is generated, and the electrodes 21 and 22 are arranged at positions where an induced voltage is obtained when blood flows through the aorta. It only has to be done. However, as described above, in terms of measurement efficiency, the exciting coil 11 is such that the three directions of the longitudinal direction of the aorta, the direction passing through the body of the magnetic field lines, and the direction connecting the two electrodes are orthogonal to each other. 12 and the electrodes 21 and 22 are preferably arranged. If the relationship between the magnetic flux and the aorta is seen, a magnetic flux that penetrates the aorta is generated.

  In the above-described embodiment, the case where the cuffs 110 and 120 are used as the peripheral arterial pulse wave measurement unit for measuring the peripheral arterial pulse wave has been described. However, the present invention is not limited thereto, and the peripheral arterial pulse wave is measured. You may perform a measurement using things other than a cuff. The peripheral arterial pulse wave can be measured by, for example, a tonometry method, a photoelectric pulse wave method, a strain sensor method, an ultrasonic method, or the like.

  Furthermore, although the case where magnetic flux was generated by the 1st and 2nd exciting coils 11 and 12 was described, not only this but magnetic flux may be generated using an exciting coil and a magnet, for example, What is necessary is just to generate the magnetic flux orthogonal to the longitudinal direction of the aorta. Similarly, in the above-described embodiment, the case where the induced voltage is detected using the two electrodes 21 and 22 has been described, but the present invention is not limited to the electrodes 21 and 22 as long as the induced voltage can be detected. As described above, one aspect of the present invention is an induced voltage generated by a magnetic flux generation unit that generates a magnetic flux toward the subject, the magnetic flux generated from the magnetic flux generation unit, and the blood flow of the subject. And a pulse wave detector for detecting a pulse wave based on the induced voltage.

  Furthermore, if the principle of the above-mentioned embodiment is used, not only the aorta but also the peripheral artery pulse wave can be measured. That is, a magnetic flux generator that generates a magnetic flux toward the peripheral artery, and an induced voltage generated by the magnetic flux generated from the magnetic flux generator and the blood flow of the peripheral artery are detected, and a peripheral pulse wave is detected based on the induced voltage. It is good also as a structure which has a pulse wave detection part. In this way, peripheral arterial pulse waves can be detected as well as aortic pulse waves. Therefore, two different arterial pulse waves can be measured by the configuration according to the two sets of the present invention, and the PWV between the two points can be obtained.

  The above-described embodiments are merely examples of implementation in carrying out the present invention, and the technical scope of the present invention should not be construed as being limited thereto. That is, the present invention can be implemented in various forms without departing from the gist or main features thereof.

  The present invention can be applied to a biological information measuring device that measures biological information such as a pulse wave velocity.

DESCRIPTION OF SYMBOLS 11, 12 Excitation coil 21, 22, 111, 121 Electrode 100 Biological information measuring device 110, 120 Cuff 130 Blood pressure pulse wave measurement part 140 Coil excitation amplification circuit part 150 Induced voltage / pulse wave measurement part 160 Electrocardiogram measurement part 170 Control / calculation Part

Claims (7)

A pulse wave measuring device for non-invasively measuring a pulse wave,
A magnetic flux generator that generates magnetic flux toward the subject;
A pulse wave detector that detects an induced voltage generated by the magnetic flux generated from the magnetic flux generator and a blood flow of the subject, and detects a pulse wave based on the induced voltage;
A pulse wave measuring apparatus comprising: First and second excitation coils arranged at positions sandwiching the body of the subject;
First and second electrodes disposed at positions sandwiching the body portion;
A coil excitation amplification circuit for supplying an excitation current to the first and second excitation coils;
A pulse wave measuring unit for detecting a pulse wave of the aorta based on an induced voltage generated between the first and second electrodes;
A pulse wave measuring apparatus comprising: The first and second exciting coils are:
Provided so that a magnetic field is focused on the aorta,
The pulse wave measuring device according to claim 2. The first and second exciting coils are Helmholtz coils, and their central axes are arranged to pass through the aorta,
The pulse wave measuring device according to claim 2 or 3. The first and second electrodes are arranged in a direction substantially perpendicular to the magnetic field generated by the first and second excitation coils and in a direction substantially perpendicular to the longitudinal direction of the aorta. Arranged,
The pulse wave measuring device according to any one of claims 2 to 4. The pulse wave measuring device according to any one of claims 1 to 5,
A peripheral arterial pulse wave measurement unit for measuring a peripheral arterial pulse wave of a subject far from the heart than a measurement point by the pulse wave measuring device;
The first timing at which blood is ejected from the heart is detected based on the aortic pulse wave obtained by the pulse wave measuring device, and the peripheral artery pulse wave is obtained based on the peripheral arterial pulse wave obtained by the peripheral arterial pulse wave measuring unit. A calculation unit that detects a second timing at which the pulse arrives at a site where the arterial pulse wave measurement unit is mounted, and calculates a pulse wave propagation time from a difference between the second timing and the first timing;
A biological information measuring device comprising: The pulse wave measuring device according to any one of claims 1 to 5,
A peripheral arterial pulse wave measurement unit for measuring a peripheral arterial pulse wave of a subject far from the heart than a measurement point by the pulse wave measuring device;
The first timing based on the pulse wave obtained by the pulse wave measurement device is detected, and the peripheral artery pulse wave measurement unit is mounted based on the peripheral artery pulse wave obtained by the peripheral artery pulse wave measurement unit. Calculating a pulse wave propagation time from a difference between the second timing and the first timing;
A biological information measuring device comprising:

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