JPH10305018A - Pulse wave propagating speed information measuring instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pulse propagating speed information measuring device capable of measuring pulse wave propagating speed information which can directly be used as an index expressing the secular change of the degree of the arteriosclerosis of a living body. SOLUTION: A time difference calculating means 82 calculates a time difference from a prescribed part generated at each cycle of an electrocardiographic induction waveform detected by an electrocardiographic inducing device 70 to a prescribed part generated at each cycle of a cuff pulse wave detected by a pressure sensor 40, and a propagating speed calculating means 84 calculates the propagating speed of the cuff pulse wave based on this time difference. Then a corrected propagating speed calculating means 86 calculates the corrected propagating speed of the cuff pulse wave corrected to a value at a fixed blood pressure value and pulse rate set in advance based on a blood pressure value measured by a blood pressure measuring means and the pulse rate measured by a pulse rate measuring means from a previously set relation. Consequently the degree of the arteriosclerosis by following the secular change of the corrected propagating speed calculated finally.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to pulse wave propagation information for measuring pulse wave propagation speed information, such as pulse wave propagation speed or pulse wave propagation time, related to the propagation speed of a pulse wave propagating in an artery of a living body. The present invention relates to a speed information measuring device.

[0002]

2. Description of the Related Art Generally, when diagnosing the degree of progression of hypertension in a hypertensive patient, a blood pressure measurement is first performed prior to the diagnosis. This method of measuring blood pressure is very effective in finding symptoms, but is not a very effective evaluation method when continuously evaluating the degree of improvement in hypertension by, for example, diet. Was. This is because chronic hypertensive patients usually take some antihypertensive drugs on a daily basis. On the other hand, utilizing the existence of arteriosclerosis as a factor affecting pulse wave propagation velocity information, for example, in order to estimate the degree of arteriosclerosis of a living body, a pulse wave propagating in an artery of the living body is used. Of the propagation speed of the object. As one of the methods, for example, a pulse wave sensor for detecting a pulse wave generated from an artery by pressing the artery from the skin of a living body is provided at two places, and a phase difference between the pulse waves detected by the pulse wave sensor is determined. There is known a method of obtaining a propagation speed based on the above. JP-A-60-220037
This is the pulse wave velocity measuring device described in Japanese Patent Publication No. According to such a device, for example, the degree of arteriosclerosis directly related to the degree of progression of hypertension can be estimated from the measured pulse wave velocity information,
Even for hypertensive patients who take antihypertensive drugs on a daily basis,
It is relatively possible to continuously assess the degree of improvement of the patient's hypertension.

[0003]

However, the pulse wave velocity information is also affected by the blood pressure value of the living body, and the blood pressure value of the living body usually shows a slightly different value each time it is measured. As a result, the measurement accuracy of the pulse wave velocity information could not be obtained sufficiently. For example, when the pulse wave velocity measured by the above-described pulse wave velocity measuring device is directly used as an index indicating a change over time in arterial stiffness, sufficient evaluation accuracy cannot be obtained.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a pulse wave velocity information measuring apparatus capable of measuring pulse wave velocity information with high accuracy. is there. For example, it is an object of the present invention to provide a pulse wave velocity information measuring apparatus that can directly use measured pulse wave velocity information as an index indicating a change over time in arterial stiffness.

[0005]

A first aspect of the present invention for achieving the above object is to provide pulse wave propagation velocity information relating to the propagation velocity of a pulse wave propagating in an artery of a living body. A pulse wave velocity information measuring device for measuring, comprising: (a) a blood pressure measuring means for measuring a blood pressure value of a living body;
(B) a first pulse wave sensor that is attached to the living body and detects a pulse wave that propagates in the artery of the living body; and (c) is attached to a downstream portion of the first pulse wave sensor and passes through the artery. A second pulse wave sensor that detects a propagating pulse wave, and (d) a second pulse wave sensor that detects the pulse wave detected by the first pulse wave sensor from a predetermined portion that is generated in each cycle. A propagation speed information calculating means for calculating pulse wave propagation speed information related to the propagation speed of the pulse wave based on a time difference to a predetermined portion generated for each cycle of the pulse wave; Based on the blood pressure value measured by the blood pressure measurement means, a corrected propagation speed information calculation means for calculating corrected propagation speed information corrected to a value at a predetermined fixed blood pressure value,
To include.

[0006]

In this way, when a pulse wave of a living body is detected by the first pulse wave sensor and the second pulse wave sensor, the pulse velocity is calculated by the propagation velocity information calculating means every period of the electrocardiographic lead waveform. The propagation velocity information of the pulse wave is calculated based on the time difference from the predetermined part to be performed and the predetermined part generated in each cycle of the pulse wave. Then, based on the blood pressure value measured by the blood pressure measuring means, the corrected propagation velocity corrected by the corrected propagation velocity information calculating means to a value at a predetermined constant blood pressure value based on the blood pressure value measured by the blood pressure measuring means. Information is calculated. Therefore, even if the blood pressure value of the living body is slightly different each time it is measured, the pulse wave propagation velocity information measured by this device is always corrected to a value at a predetermined fixed blood pressure value. Since the information is the propagation velocity information, it is possible to directly use the measured pulse wave propagation velocity information as an index indicating a temporal change in the degree of arteriosclerosis.

[0007]

According to a second aspect of the present invention, there is provided a pulse rate measuring means for measuring a pulse rate of the living body, and
The corrected propagation velocity information calculating means is configured to set a predetermined blood pressure based on a blood pressure value measured by the blood pressure measuring means and a pulse rate measured by the pulse rate measuring means from a preset relationship. It is characterized in that corrected propagation velocity information corrected to a value at a value and a pulse rate is calculated.

[0008]

In this way, in addition to the effect of the first aspect, the corrected propagation velocity information measured by this device is not affected by the pulse rate, so that higher accuracy can be obtained. For this reason, for example, when the measured pulse wave propagation velocity information is used as an index indicating a change over time in the degree of arteriosclerosis, more accurate evaluation can be performed.

[0009]

According to a third aspect of the present invention, there is provided: (h) propagation speed information calculated by the propagation speed information calculating means and the blood pressure measuring means. Including a coefficient value determining means for determining a coefficient value that changes corresponding to the blood pressure value measured by,
(I) The corrected propagation velocity information calculating means multiplies a difference between a predetermined fixed blood pressure value and a blood pressure value measured by the blood pressure measuring means by a coefficient value determined by the coefficient value determining means. On the basis of the above, corrected propagation speed information corrected to a value at a predetermined fixed blood pressure value is calculated.

[0010]

According to the third aspect of the invention, in addition to the effect of the first aspect of the invention, the corrected propagation speed information measured by this device is obtained by comparing the propagation speed information calculated by the propagation speed information calculating means with the blood pressure measurement. Since the coefficient is calculated using a coefficient determined according to the blood pressure value measured by the means, that is, a coefficient that also takes into account the influence of individual differences in arterial stiffness, higher accuracy can be obtained. For this reason, for example, the measured pulse wave propagation velocity information can be used as an index indicating individual differences in arterial stiffness.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a perspective view showing an automatic blood pressure measurement device 8 including a pulse wave propagation velocity information measurement device for automatically measuring a blood pressure value of a living body.

In FIG. 1, a box 10 is provided with a through hole 14 into which a right arm 12 of a subject is inserted. In the through hole 14, a bag-shaped flexible cloth and a rubber bag are provided. A belt 16 which is provided with a cuff 15 formed on the inner peripheral surface thereof and held in a cylindrical shape is provided. A first armrest 17 for supporting the right arm 12 of the subject protruding from the through-hole 14 is provided in an uphill shape in the rear direction of the through-hole 14, and a tip portion of the first armrest 17 is provided. The electrode 18 is connected to the right arm 12 of the subject in order to detect an electrocardiographic waveform generated with the activity of the subject's heart.
It is arranged to make good contact with the back of the hand. The first armrest 17 keeps the muscle from the elbow of the right arm 12 of the subject to the back of the hand constantly relaxed so that an accurate ECG waveform can be always detected from the back of the subject's hand. It has an optimal support surface shape that supports the entire area from the elbow to the back of the hand so that it can lean. On the left side of the box 10, a second armrest 19 for supporting the left arm 13 of the subject is provided.
An electrode 18 is disposed substantially at the center of the armrest 19 so as to contact the left arm 13 of the subject in order to detect the electrocardiographically induced wave of the subject. Note that this second
Like the first armrest 17, the armrest 19 also has an optimal support surface shape that supports the entire area from the elbow to the hand so that the muscle of the left arm 13 of the subject can be constantly relaxed. ing. An operation switch 20, a stop switch 24, a printer 26, a card slot 28, and the like are provided on an operation panel 20 of the box 10, and a systolic blood pressure indicator 32 and a diastolic blood pressure indicator 3 are provided on a display panel 30.
4. A pulse rate display 36 and a time display 38 are provided.

FIG. 2 is a block diagram for explaining a circuit configuration of the automatic blood pressure measuring device 8. In the figure, cuff 1
5 is connected to a pressure sensor 40, a switching valve 42, and an air pump 44 via a pipe 46.
2 includes three states: a pressure supply state in which the supply of pressure into the cuff 15 is allowed, a slow discharge state in which the cuff 15 is gradually discharged, and a rapid discharge state in which the cuff 15 is rapidly discharged. It is configured to be switchable. Further, the cuff 15 is provided on the inner peripheral surface, and the belt 16 is wound in a cylindrical shape.
Is fixed at one end and the other end is a DC motor 48 with a reduction gear.
It is configured to be tightened by the drum 50 driven by the. The pressure sensor 40 detects the pressure in the cuff 15 and supplies a pressure signal SP representing the pressure to the static pressure discrimination circuit 52 and the pulse wave discrimination circuit 54, respectively.

The static pressure discriminating circuit 52 includes a low-pass filter, discriminates a cuff pressure signal SK representing a steady pressure included in the pressure signal SP, ie, a cuff pressure, and converts the cuff pressure signal SK into an A / D converter 56. To the electronic control unit 58 via The pulse wave discrimination circuit 54 includes a band-pass filter, and a pulse wave signal S which is a vibration component of the pressure signal SP.
The pulse wave signal SM ₁ to discriminate the M ₁ in frequency A / D
The electric power is supplied to the electronic control device 58 via the converter 60. The cuff pulse wave represented by the pulse wave signal SM ₁ is a pressure vibration wave generated from an unshown brachial artery and transmitted to the cuff 15 in synchronization with the heartbeat of the subject, and includes the cuff 15 and the pressure sensor 4.
0, and the pulse wave discrimination circuit 54 detects a pulse wave propagating in the artery at a position downstream of the first pulse wave sensor.
It functions as a pulse wave sensor.

The electronic control unit 58 includes a CPU 62, R
The CPU 62 is configured by a so-called microcomputer including an OM 64, a RAM 66, and an I / O port (not shown). The CPU 62 processes an input signal according to a procedure stored in the ROM 64 in advance while using the temporary storage function of the RAM 66. To output drive signals and display signals. That is, when measuring the blood pressure, the CPU 62 drives the DC motor 48 with a speed reducer in accordance with a predetermined procedure to wind the cuff 15 around the upper arm of the living body, and drives the air pump 44 to cause the cuff 15 to move the upper arm. Portion, and then the switching valve 42 is driven to gradually reduce the compression pressure of the cuff 15. Based on the pulse wave signal SM ₁ and the cuff pressure signal SK obtained in the slow down process, the blood pressure is oscillometrically determined. The value is determined, and the blood pressure value is displayed on the systolic blood pressure display 32 and the diastolic blood pressure display 34, and at the same time, sequentially stored in the blood pressure value storage area of the storage device 68. The storage device 68 is constituted by a well-known storage device such as a magnetic disk, a magnetic tape, a volatile semiconductor memory, or a nonvolatile semiconductor memory.

The electrocardiography device 70 is connected to the right arm 12 of the subject.
And a so-called electrocardiogram continuously indicating an action potential of the myocardium through a pair of electrodes 18 which are brought into contact with the back of the hand and the left arm 13. Supply to device 58. Since the electrocardiographic lead waveform, particularly the R wave, corresponds to the rising point at the starting point of the aortic pressure waveform, the electrocardiographic lead device 7
Numeral 0 functions as a first pulse wave sensor for periodically detecting a pulse wave at the most upstream part in the artery.

FIG. 3 is a functional block diagram for explaining a main part of the control function of the electronic control unit 58 in the automatic blood pressure measurement device 8. In the figure, the pressure increase control means 78 first switches the switching valve 42 to the pressure supply state and drives the air pump 44 to reduce the compression pressure of the cuff 15 to a predetermined target cuff pressure value P ₁ (for example, about 180 mmHg). (Pressure value), and the switching pressure of the cuff 15 is gradually reduced by switching the switching valve 42 to the slow exhaust pressure state. After the blood pressure measurement is completed, the switching valve 42 is switched to the rapid exhaust pressure state. Thereby, the compression pressure of the cuff 15 is rapidly discharged. The blood pressure measuring means 80 performs the compression pressure changing process of gradually decreasing the compression pressure of the cuff 15,
The systolic blood pressure value SBP and the minimum blood pressure value of the subject are measured by a well-known oscillometric method based on a change in the amplitude of the cuff pulse wave collected by the pulse wave discriminating circuit 54 via the pressure sensor 40 (corresponding to a pulse wave sensor). The blood pressure value DBP is measured.
Further, the pulse rate measuring means 81 calculates a pulse rate HR based on the cuff pulse wave generation interval. Time difference calculation means 82
When the compression pressure of the cuff 15 is near the pressure at which the diastolic blood pressure value DBP is measured, the electrocardiographic lead-in device is started from a predetermined portion generated every cycle of the cuff pulse wave detected by the pressure sensor 40. time difference to a predetermined site occurring every period of the ECG waveform detected by 70, for example, the time difference TD _RP from R-wave of the ECG waveform as shown in FIG. 5 to the maximum value of the cuff pulse wave Is calculated.

The propagation speed calculating means 84 calculates the time difference TD actually calculated from the preset equation (1).
Based on the _RP , a propagation speed V _M1 (m / sec), which is the propagation speed information of the cuff pulse wave, is calculated. In Equation 1, L is the distance (m) from the left ventricle via the aorta to the pressed portion of the pressure sensor 40, and T _PEP is the pre-ejection period from point Q of the electrocardiographic lead waveform to the rising point of the cuff pulse wave. (Sec). These distance L and pre-ejection period T
A value experimentally obtained in advance is used for _PEP . In the present embodiment, the time difference calculating means 82 and the propagation velocity calculating means 84 function as pulse wave propagation velocity information calculating means.

[0019]

## EQU1 ## _VM1 = L / ( _TDRP - _TPEP )

The corrected propagation velocity calculating means 86, which functions as the corrected pulse wave propagation velocity information calculating means, calculates the minimum blood pressure value DBP measured by the blood pressure measuring means 80 and the pulse rate based on the measured pulse rate HR by measuring means 81, preset constant pressure value BP _t and pulse rate HR said corrected to the value at _t cuff pulse wave modification propagation velocity V _M2 (m / sec) is Is calculated. In Equation 2, the coefficient A is predetermined by the coefficient value determining means 87 based on Equation 3, and is a coefficient value that changes in proportion to the propagation speed V _M1 and inversely proportional to the diastolic blood pressure value DBP. Where the constants B, C and D in Equation 3
Also, the constant E in Equation 2 is experimentally obtained in advance.

[0021]

[Number 2] _{V M2 = V M1 + A (} BP t -DBP) + E (HR
_t- HR)

[0022]

A = BV _M1 −C (DBP) + D

FIG. 4 is a flowchart for explaining a main part of the control operation of the electronic control unit 58. In step SA1 in the figure (hereinafter, the steps are omitted), it is determined whether or not the magnetic card 74 has been inserted into the card insertion slot 28 of the card reading device 72. If the determination in step SA1 is denied, this routine is ended. If the determination is affirmed, the magnetic card 74 is determined in SA2.
Is read.

In the subsequent SA3, it is determined whether or not the read ID signal has been registered in the storage area of the storage device 68 in advance. If the determination in SA3 is denied, that is, if the ID signal recorded on the magnetic card 74 has not been registered, SA21 described later is executed and the magnetic card 74 is sent out from the card insertion slot 28. However, when the determination in SA3 is affirmed, that is, when the magnetic card 7
If the ID signal recorded in No. 4 has already been registered,
In A4, it is determined whether the activation switch 22 for measuring blood pressure has been operated.

If the determination at SA4 is denied, the process waits until it is affirmed. However, if the determination in SA4 is affirmative, SA5 and SA6 corresponding to the boost control means 78 are executed. First, at SA5, the switching valve 42 is switched to the pressure supply state and the air pump 4
4 is driven and the cuff pressure P is set to a preset target cuff pressure P.
_After the pressure is increased to ₁ (for example, a pressure of about 180 mmHg), the air pump 44 is stopped. Next, SA6
, The switching valve 42 is switched to the slow exhaust state, whereby the slow pressure reduction in the cuff 15 is started.

Subsequently, at SA7, the pulse wave signal SM
₁ is read, and it is determined whether or not one pulse wave is detected. If this determination is denied, SA7 is repeatedly executed.
Is executed, the blood pressure value determination routine of SA8 corresponding to is executed.
In this blood pressure value determination routine, based on the change in the amplitude of the pulse wave sequentially detected during the slow down process of the cuff pressure P,
The systolic blood pressure value SBP ₁ and the diastolic blood pressure value DBP according to a well-known oscillometric blood pressure value determining algorithm.
₁ and the average blood pressure value MBP ₁ are determined, and the pulse rate HR ₁ is determined based on the pulse wave interval.

Next, in SA9, the systolic blood pressure value SBP
₁ Is determined. This judgment is denied
In the case where it is found, SA7 to SA9 are repeatedly executed.
However, if this judgment is affirmed, the subsequent SA10
In the diastolic blood pressure value DBP ₁ Is determined whether or not
Refused. If this determination is denied, SA7 through S7
A10 is repeatedly executed. However, this judgment is affirmative
In the subsequent SA11, the measured
The highest blood pressure SBP₁ , Diastolic blood pressure DBP₁ , Mean blood pressure
Value MBP₁ , And pulse rate HR₁ And measurement date and time
Is stored for each subject in the blood pressure value storage area of the device 68.
Both systolic blood pressure indicator 32, diastolic blood pressure indicator 34, pulse rate
The information is displayed on the display 36.

Then, by executing the following SA12, the electrocardiogram waveforms sequentially detected by the electrocardiograph 68 are read, and the cuff pulse waves sequentially detected by the pressure sensor 40 are read at SA13. . Next, in SA14, the R wave (R
Is detected. If this determination is denied, the above-mentioned SA12 and subsequent steps are repeatedly executed. If the determination is affirmative, it is determined whether or not the maximum point of the cuff pulse wave has been detected in subsequent SA15.

If the determination at SA15 is denied, the above-mentioned SA12 and subsequent steps are repeatedly executed. If the determination is affirmed, at SA16 corresponding to the boost control means 78, the switching valve 42 is switched to the rapid exhaust state. As a result, a rapid pressure drop in the cuff 15 is started. At SA17 corresponding to subsequent said time difference calculating means 82, as shown in FIG. 5, the time difference TD _RP from R-wave of the ECG waveform to a maximum value of the cuff pulse wave is calculated. Subsequently, in SA18 corresponding to the propagation speed calculation means 84, the propagation speed V _M1 of the cuff pulse wave is calculated based on the time difference TD _RP actually obtained in SA17 from Equation 1 stored in advance.

Subsequently, in SA19 corresponding to the coefficient value determining means 87, the propagation velocities V _M1 and SA8 calculated in SA18 are calculated based on the equation 3 stored in advance.
Is determined from the diastolic blood pressure value DBP measured in the above. Next, the corrected propagation velocity calculating means 86
Corresponding to the SA20, from the formula 2, which is pre-stored, based on the diastolic blood pressure DBP and pulse rate HR measured at SA8, the above constant of the cuff pulse wave is preset blood pressure BP _t and the pulse rate HR A corrected propagation velocity V _M2 corrected to the value at _t , that is, normalized, is calculated.

Subsequently, in SA21, for example, FIG.
As shown in the figure, the systolic blood pressure value SBP _{1 and the} like are displayed and output on the recording paper 90 by the printer 26. That is, the name 92 of the subject is displayed at the upper left position on the recording paper 90.
Together but appear, in its lower side, date and time of measurement, a blood pressure value, pulse rate, and the corrected propagation velocity V _M2 arterial stiffness of the list 94 is determined in accordance with Figure 7 from the trend graph 96 are sequentially displayed . As a method of determining the degree of arteriosclerosis, for example, it is determined by selecting a predetermined value of the degree of arteriosclerosis according to the calculated value of the corrected propagation velocity _VM2 based on a table as shown in FIG. This table is experimentally determined in advance, and the artery of the subject loses its flexibility as the value of the arteriosclerosis degree increases.
In the trend graph 96, the bar line indicating the systolic blood pressure value and the diastolic blood pressure value at the upper end and the lower end respectively, the mark 脈 indicating the pulse rate, and the mark ● indicating the arteriosclerosis degree correspond to the blood pressure measurement time on the horizontal axis, that is, the time. Displayed along axis 98.
Then, by executing the subsequent SA22, the magnetic card 74 is sent out from the card insertion slot 28.

As described above, according to this embodiment, the time difference
The electrocardiogram is obtained by SA17 corresponding to
The cuff pulse wave starts from a predetermined position that is generated every cycle of the shape.
Time difference TD to a predetermined site that occurs every period_RPIs calculated
The SA 18 corresponding to the propagation velocity calculating means 84
Of the pulse wave based on the time difference_M1Is calculated
You. Then, the SA corresponding to the corrected propagation speed calculating means 86
20, the blood pressure measurement is calculated from Equation 2 stored in advance.
By means of SA8 corresponding to the means 80 and the pulse rate measuring means 81
Based on measured diastolic blood pressure value DBP and pulse rate HR
A predetermined blood pressure value BP_tAnd pulse rate H
R_tCorrected propagation velocity V corrected to the value at _M2Is calculated
You. Therefore, even if the blood pressure value and pulse rate of the living body are measured,
This device, even if it is slightly different each time
The calculated pulse wave velocity is always a predetermined blood pressure value and
Corrected propagation velocity when pulse and pulse rate were measured
Since the measured pulse wave velocity is
Can be used directly as an index to indicate changes over time in
Become.

In addition, the calculated corrected propagation velocity V _M2 is
Preset constant blood pressure value BP _t and pulse rate HR _t
Since those that have been modified to a value of, based on Equation 4, when compared to only one it has been corrected to a preset value at constant blood pressure BP _t was, by an amount affected by the pulse rate is eliminated, and more More accurate evaluation is possible.

[0034]

[Equation 4] _{V M2 = V M1 + A (} BP t -DBP)

Moreover, the corrected propagation velocity V _M2 measured by this device is calculated by the SA1 corresponding to the coefficient value determining means 87.
In step 9, based on equation 3 stored in advance, SA1
8, which is calculated using the coefficient A determined from the propagation velocity V _M1 calculated in step 8 and the diastolic blood pressure value DBP measured in SA8, that is, a coefficient that also takes into account the effects of individual differences in arterial stiffness. Therefore, the measured pulse wave propagation velocity can be used as an index indicating individual differences in arterial stiffness.

Further, according to the automatic blood pressure measuring device 8 of this embodiment, the pulse wave velocity is measured simultaneously with the blood pressure measurement, and the pulse wave velocity is directly used as an index indicating the temporal change of the arterial stiffness. Since the data is converted so that it can be used, more biological information is provided to the subject, and the health condition can be more diversified. Further, the degree of arterial stiffness corresponding to the calculated pulse wave velocity is displayed as a trend graph, so that a temporal change can be more easily and accurately grasped.

In addition, since the pulse wave propagation velocity has conventionally been measured by attaching a pulse wave sensor to the carotid artery and the hip artery using a dedicated fixing device, considerable skill has been required in searching for an optimal pressure. In short, although it was quite difficult for the subject to measure himself, the automatic blood pressure measurement device 8 of this embodiment
According to the method, the pulse wave propagation velocity can be easily measured without special skill, so that the subject can measure the pulse wave velocity.

Further, according to this embodiment, when the pressing pressure of the cuff 15 is near the same pressure as the diastolic blood pressure DBP _1,
Using cuff pulse wave detected by the pressure sensor 40, in SA16 corresponding to the time difference calculating means 82, the time difference TD _RP and R-wave of the maximum value and the ECG waveform of the cuff pulse wave is calculated. Generally, in a period of the compression pressure is more than the mean blood pressure value of the cuff 15, but the time difference TD _RP is known to decrease with decreasing pressing pressure of the cuff 15, the time difference TD _RP is pressure of the cuff 15 The measured time difference TD _RP is very accurate because it was measured at a time when it was hardly affected by the change in pressure.
Finally, SA20 corresponding to the corrected propagation velocity calculating means 86
The accuracy of the corrected propagation speed V _M2 calculated in is very good.

Although the embodiment of the present invention has been described with reference to the drawings, the present invention can be applied to other embodiments.

For example, in the above-described embodiment, the case where the pulse wave velocity V _M1 or V _M2 is used as the pulse wave velocity information has been described, but the propagation time TD directly corresponding to the pulse wave velocity is used. _RP could be used instead. In this case, the propagation speed calculating means 84 and the SA 18 corresponding thereto are unnecessary. Further, in this case, instead of modifying the propagation velocity calculating means 86, corrected pulse wave velocity information calculation means or corrected pulse wave propagation time calculating means for modifying the pulse wave propagation time TD _RP based on the pulse rate HR Is used. In this modified pulse wave transit time calculating means,
For example, according to Equations 5 and 6, the blood pressure measurement unit 8
Blood pressure value DBP measured by zero and pulse wave measuring means 8
The corrected pulse wave velocity TD _{RP 2} is calculated based on the pulse rate HR measured in Step 1.

[0041]

TD _RP2 = (TD _RP −T _PEP ) L / ｛L + A ′
(BP _t −DBP) + E (HR _t −HR)｝

[0042]

A ′ = B × L / (TD _RP −T _PEP ) −C (DBP) + D

In the above-described embodiment, the pulse wave propagation velocity V _M1 is calculated from Equation 1 based on the time difference TD _RP from the R wave of the electrocardiographic lead waveform to the maximum value of the cuff pulse wave. The time difference TD _RP is a time difference between the Q wave or S wave of the electrocardiographic lead waveform and the maximum value of the cuff pulse wave, and a time difference between the Q wave or R wave of the electrocardiographic lead waveform and the minimum value or the rising point of the cuff pulse wave. And so on.

Further, in the equation 1 of the above-described embodiment, T
_{The PEP} was defined as the pre-ejection period (sec) from the Q point of the electrocardiographic lead waveform to the rising point of the cuff pulse wave, but the _PEP was defined from the R or S point of the electrocardiographic lead waveform to the rising point of the cuff pulse wave. It may be defined as a pre-ejection period. Since the mutual time difference between the Q point, the R point, and the S point in the electrocardiographic waveform is an extremely small value, it may be defined as in the above-described embodiment.

In the above-described embodiment, the right arm 12
Was configured to be inserted into the through hole 14,
The left arm 13 may be configured to be inserted into the through hole 14, and in this case, the through hole 14, the first armrest 17, the second armrest 19, and the like are provided at opposite positions. Further, in the above embodiment,
The first armrest 17 was provided in an uphill shape,
Alternatively, the second armrest may be provided in a horizontal shape, and conversely, the second armrest may be provided in an uphill shape. In short, it is only necessary that the muscles be designed so as to maintain a relaxed state.

In the above-described embodiment, the electrode 18 is connected to the tip of the first armrest 17 and the second armrest 19.
Is provided at the center of the armrest, but it is not necessary to be limited to this position. The position can be changed to various positions depending on the shape and the position of the armrest. In short, right arm 12
What is necessary is just to be installed so that a stable electrocardiographic waveform can be detected from the left arm 13 and the left arm 13.

Further, in the above-described embodiment, the calculated corrected propagation velocity V _M2 is a predetermined fixed blood pressure value B
P _t and it was those modified to a value in the pulse rate HR _t, corrected propagation velocity V _M2 to be calculated based on the equation 4, only the pre-set value at constant blood pressure BP _t fix It may be done. Since the effect of the pulse rate on the pulse wave velocity is not as great as the effect of the blood pressure value, a necessary and sufficient effect can be obtained.

In the above-described embodiment, the cuff 15
Is automatically wound around the arm of the person to be measured, but an automatic blood pressure measuring device of the type in which the person is wound around the arm by himself is adopted. No problem.

In addition, Equation 3 of the above-described embodiment can provide the same effect as Equation 7. In short, this formula determines the coefficient value A that is proportional to the propagation speed V _M1 calculated by the propagation speed calculation means 84 and inversely proportional to the diastolic blood pressure value DBP measured by the blood pressure measurement means 74. It is good if you can.

[0050]

(Equation 7)

In the above-described embodiment, the cuff 15 for detecting the cuff pulse wave, the pressure sensor, and the pulse wave discrimination circuit 54 function as the second pulse wave sensor. Radial pulse wave sensor that detects the pressure pulse wave
A photoelectric pulse wave sensor that detects the pulse wave of the arteriole of the fingertip using light may be used.

In the above-described embodiment, the electrocardiogram guiding device 7
Although 0 functions as the first pulse wave sensor, a carotid artery wave sensor that detects a pulse wave of the carotid artery, a brachial artery sensor that detects a pulse wave of the brachial artery, or the like is used as the first pulse wave sensor. Good.

The present invention can be modified in various other ways without departing from the gist thereof.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating an automatic blood pressure measurement device 8 according to an embodiment of the present invention.

FIG. 2 is a block diagram illustrating a circuit configuration of the embodiment of FIG. 1;

FIG. 3 is a functional block diagram illustrating a main part of a control function of the electronic control device 58 of the embodiment in FIG. 1;

FIG. 4 is a flowchart illustrating a main part of a control operation of the electronic control device 58 of the embodiment in FIG. 1;

FIG. 5 is a time chart for explaining a time difference TD _RP obtained by the control operation of the embodiment of FIG. 1;

6 is a diagram showing an example of a display output by the printer 26 of the embodiment in FIG.

FIG. 7 is a diagram showing an example of a table used when converting the measured pulse wave propagation velocity into a predetermined arteriosclerosis degree.

[Explanation of symbols]

 8: Automatic blood pressure measurement device 15: Cuff 18: Electrode 40: Pressure sensor 70: Electrocardiography device 78: Boost control device 80: Blood pressure measurement device 81: Pulse rate measurement device 82: Time difference calculation device 84: Propagation speed calculation device 86 : Modified propagation speed calculation means 87: Coefficient value determination means

Claims (3)

[Claims] A pulse wave velocity information measuring device for measuring pulse wave velocity information related to a pulse wave velocity propagating in an artery of a living body, wherein the blood pressure measurement measures a blood pressure value of the living body. Means, a first pulse wave sensor attached to the living body for detecting a pulse wave propagating in the artery of the living body, and a pulse attached to a downstream portion of the first pulse wave sensor and propagating in the artery. A second pulse wave sensor for detecting a wave, and a predetermined portion generated for each period of the pulse wave detected by the first pulse wave sensor, for each period of the pulse wave detected by the second pulse wave sensor. A propagation speed information calculating unit that calculates pulse wave propagation speed information related to the propagation speed of the pulse wave based on a time difference up to a predetermined site to be generated; A fixed blood pressure value set in advance based on the blood pressure value A modified propagation velocity information calculation means for calculating the corrected propagation speed information obtained by correcting the definitive value, pulse-wave-propagation-velocity-related-information obtaining device which comprises 2. A pulse rate measuring means for measuring a pulse rate of the living body, wherein the corrected propagation speed information calculating means calculates a blood pressure value measured by the blood pressure measuring means from a preset relationship, and 2. The pulse wave propagation velocity information measurement according to claim 1, wherein corrected propagation velocity information corrected to a predetermined fixed blood pressure value and a value at the pulse rate is calculated based on the pulse rate measured by the number measuring means. apparatus 3. The corrected propagation according to claim 1, further comprising: a coefficient value determining unit that determines a coefficient value that changes in accordance with the propagation speed information calculated by the propagation speed information calculating unit and a blood pressure value measured by the blood pressure measuring unit. The speed information calculation unit is configured to multiply a difference between a predetermined blood pressure value set in advance and the blood pressure value measured by the blood pressure measurement unit by a coefficient value determined by the coefficient value determination unit. 2. The pulse wave propagation velocity information measuring device according to claim 1, wherein the apparatus calculates corrected propagation velocity information corrected to a value at a set constant blood pressure value.