JP3649464B2 - Cardiac function evaluation device - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a cardiac function evaluation apparatus for evaluating the blood ejection function of a living heart.
[0002]
[Prior art]
The blood ejection function of the living heart increases in accordance with the exercise load applied to the living body, and has a property of recovering toward a resting state when the exercise load is eliminated. For example, since the blood ejection volume of the heart is determined by the stroke volume SV (Stroke Volume) × heart rate HR (Heart Rate) per beat, the stroke volume is assumed on the assumption that the peripheral resistance does not change so much. The blood pressure value reflecting the SV is measured before and after the exercise load is applied, and the change in the exercise load before and after the exercise load and the recovery state after the exercise load are applied to estimate the blood ejection function of the heart and the presence or absence of the disease. Can be used as reference data.
[0003]
[Problems to be Solved by the Invention]
By the way, one type of heart disease is called painless myocardial ischemia. Since such a disease is unconscious, it is desired to enable a highly accurate diagnosis. However, in the case of myocardial ischemia as described above, since there is a property that the cardiac function, that is, the stroke volume is reduced, even if trying to determine the blood ejection function of the heart using the heart rate HR as described above, There was a drawback that an accurate determination could not be made.
[0004]
The present invention has been made against the background described above, and an object of the present invention is to provide a cardiac function evaluation apparatus capable of accurately evaluating cardiac function.
[0005]
As a result of various investigations on the basis of the above circumstances, the present inventors show that the progenitor period from the point Q of the electrocardiogram-induced waveform to the rising point of the pulse wave in the aorta is closely related to cardiac function. I found. In other words, since the myocardial contraction is weakened in the myocardial ischemia state, the rising point of the pulse wave tends to be delayed and the precursor emission period tends to be longer. The present invention has been made based on the above findings.
[0010]
[ Means for Solving the Problems]
The gist of the present invention is a cardiac function evaluation apparatus for evaluating the blood ejection function of the heart of a living body, and (a) an electrocardiographic induction apparatus that detects an electrocardiographic induction waveform of the living body; b) A pair of pulse wave sensors that are mounted at two predetermined locations on the living body and detect pulse waves generated at these two locations, respectively, and (c) (c1) the pair of pulse wave sensors, respectively. A time difference calculating means for calculating the generated pulse wave time difference, and (c2) a rising point estimating means for estimating the rising point of the pulse wave in the aorta based on the pulse wave generation time difference calculated by the time difference calculating means; , (c3) means out Q inspection substantially detect Q point of the ECG waveform, (c4) from a preset relationship, the Q point detecting the rising point estimation and Q points detected by means before based on the rising point of the pulse wave estimated by the means And a pre-ejection period calculation means for calculating the pre-ejection period, on the basis of the detection point of the detected pulse wave and the point Q of the detected ECG waveform by the ECG device by said pulse wave sensor, A precursor period measuring means for calculating a precursor period of the heart from a point Q of the electrocardiogram-induced waveform to a rising point of the pulse wave in the aorta of the heart, and (d) by the precursor period measuring means And an evaluation means for evaluating the cardiac function of the heart based on the measured precursor release period.
【The invention's effect】
In this way, since the cardiac function is evaluated based on the precursor release period that is directly related to the ischemic state of the myocardium, an accurate evaluation result of the cardiac function can be obtained. In addition, since the precursor ejection period is calculated based on the point Q and the pulse wave generation time difference, the accuracy of the precursor ejection period is improved.
[0011]
Here, preferably, the precursor emission period measuring unit includes a rising point estimating unit that estimates a rising point of the pulse wave in the aorta based on a generation time difference of the pulse wave calculated by the time difference calculating unit, The precursor emission period is calculated based on the Q point detected by the Q point detecting means and the rising point of the pulse wave in the aorta estimated by the rising point estimating means. In this way, the precursor emission period is calculated based on the Q point detected by the Q point detection means and the rising point of the pulse wave in the aorta estimated by the rising point estimation means. The period can be calculated accurately and easily.
[0012]
【Example】
Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a diagram illustrating a configuration when a cardiac function evaluation device is provided together with a blood pressure monitoring device 8.
[0013]
In FIG. 1, the blood pressure monitoring device 8 has a rubber bag in a cloth belt-like bag and is connected to the cuff 10 wound around the upper arm 12 of a patient, for example, and connected to the cuff 10 via a pipe 20. A pressure sensor 14, a switching valve 16, and an air pump 18 are provided. The switching valve 16 has a pressure supply state that allows supply of pressure into the cuff 10, a slow discharge state that gradually discharges the inside of the cuff 10, and a quick discharge state that rapidly discharges the inside of the cuff 10. It is configured to be switched to one state.
[0014]
The pressure sensor 14 detects the pressure in the cuff 10 and supplies a pressure signal SP representing the pressure to the static pressure discrimination circuit 22 and the pulse wave discrimination circuit 24, respectively. The static pressure discriminating circuit 22 includes a low-pass filter, discriminates a cuff pressure signal SK representing a steady pressure, that is, a cuff pressure included in the pressure signal SP, and electronically controls the cuff pressure signal SK via an A / D converter 26. Supply to device 28.
[0015]
The pulse wave discriminating circuit 24 includes a band-pass filter, which discriminates in frequency the pulse wave signal SM ₁ which is a vibration component of the pressure signal SP, and electronically controls the pulse wave signal SM ₁ via the A / D converter 30. Supply to device 28. The cuff pulse wave represented by the pulse wave signal SM ₁ is a pressure vibration wave generated from the brachial artery (not shown) and transmitted to the cuff 10 in synchronization with the heartbeat of the patient. The cuff pulse wave, the pressure sensor 14, and the pulse The wave discrimination circuit 24 functions as a cuff pulse wave sensor 70 described later.
[0016]
The electronic control unit 28 includes a CPU 29, a ROM 31, a RAM 33, and a so-called microcomputer having an I / O port (not shown). The CPU 29 has a storage function of the RAM 33 according to a program stored in advance in the ROM 31. By executing signal processing while using, a drive signal is output from the I / O port to control the switching valve 16 and the air pump 18.
[0017]
The pressure pulse wave detection probe 34 is in a state where the open end of the container 36 is opposed to the body surface 38 at the wrist 42 on the downstream side of the artery of the upper arm 12 with or without the cuff 10 attached. The attachment band 40 is detachably attached to the wrist 42. A pressure pulse wave sensor 46 is provided inside the housing 36 through a diaphragm 44 so as to be relatively movable and projectable from the open end of the housing 36. A pressure chamber 48 is formed by the housing 36 and the diaphragm 44 and the like. Has been. In the pressure chamber 48, pressure air is supplied from the air pump 50 via the pressure regulating valve 52, so that the pressure pulse wave sensor 46 has a pressing force P corresponding to the pressure in the pressure chamber 48. It is pressed against the body surface 38 by _HD .
[0018]
The pressure pulse wave sensor 46 is configured by, for example, a large number of semiconductor pressure-sensitive elements (not shown) arranged on a pressing surface 54 of a semiconductor chip made of single crystal silicon or the like. By being pressed onto the radial artery 56, a pressure vibration wave generated from the radial artery 56 and transmitted to the body surface 38, that is, a pressure pulse wave, is detected, and a pressure pulse wave signal SM ₂ representing the pressure pulse wave is detected. Is supplied to the electronic control unit 28 via the A / D converter 58.
[0019]
The CPU 29 of the electronic control unit 28 outputs drive signals to the air pump 50 and the pressure regulating valve 52 in accordance with a program stored in advance in the ROM 31 to press the pressure in the pressure chamber 48, that is, the pressure pulse wave sensor 46 against the skin. Adjust pressure. Thereby, in the continuous blood pressure monitoring, the optimum pressing force P _HDP of the pressure pulse wave sensor 46 is determined based on the pressure pulse wave sequentially obtained in the pressure change process in the pressure chamber 48, and the optimum pressing force of the pressure pulse wave sensor 46 is determined. The pressure regulating valve 52 is controlled so as to maintain the pressure P _HDP .
[0020]
The electrocardiographic induction device 60 continuously detects an electrocardiographic induction waveform indicating an action potential of the myocardium, that is, an electrocardiogram, via a plurality of electrodes 62 attached to a predetermined part of a living body. ECG waveform) is supplied to the electronic control unit 28.
[0021]
FIG. 2 is a functional block diagram illustrating a main part of the control function of the electronic control device 28 that controls the cardiac function evaluation device of the present embodiment and the blood pressure monitoring device 8. In the figure, the blood pressure measuring means 72 is well known on the basis of the change in the magnitude of the pulse wave collected by the pulse wave discrimination circuit 24 in the process of changing the compression pressure for gradually increasing or decreasing the compression pressure of the cuff 10. The patient's systolic blood pressure SAP and diastolic blood pressure DAP are measured by the oscillometric method (JIS T 1115). The cuff pulse wave sensor 70 is a cuff pulse wave that is a pressure vibration generated in synchronization with the heartbeat in the cuff 10 in a state where the cuff 10 is preferably maintained at a predetermined pressure lower than the minimum blood pressure value. Is detected.
[0022]
The pressure pulse wave sensor 46 preferably detects a pressure pulse wave generated from the radial artery of the wrist by being pressed against the wrist of the same arm as the arm on which the patient's cuff 10 is worn. The pressure pulse wave blood pressure correspondence determining means 74 is a correspondence between the pressure pulse wave magnitude P _M detected by the pressure pulse wave sensor 46 and the blood pressure value (monitored blood pressure value MBP) measured by the blood pressure measuring means 72. A relationship is predetermined for a given patient. This correspondence is shown in FIG. 3, for example, and is represented by the expression MBP = A · P _M + B. Here, A is a constant indicating the slope, and B is a constant indicating the intercept. The monitoring blood pressure value determining means 76 determines the magnitude P _{M of the} pressure pulse wave detected by the pressure pulse wave sensor 46 from the correspondence relationship, that is, the highest value (upper peak value) P _M2max and the lowest value (lower peak value) P _M2min . Based on this, the systolic blood pressure value MBP _SYS and the diastolic blood pressure value MBP _DIA (monitor blood pressure value) are sequentially determined, and the determined monitoring blood pressure value MBP is continuously output to the display 32.
[0023]
The precursor emission period measuring means 78 includes a Q point detecting means 80, a time difference calculating means 82, a rising point estimating means 84, and a precursor emission period calculating means 86, and from the Q point of the electrocardiographic induction waveform to the aorta of the heart. The pre-ejection period (PEP) of the heart during the period up to the rising point of the pulse wave is measured. Then, the evaluation unit 88 evaluates the cardiac function of the heart based on the precursor period PEP measured by the precursor period measuring unit 78.
[0024]
The Q point detection means 80 detects the Q point of the electrocardiogram waveform detected by the electrocardiograph 60, that is, the lowest point of the Q wave (time T _Q ). In the ECG waveform, the Q point, which is the lowest point of the Q wave, the R point, which is the highest point of the R wave, and the S point, which is the lowest point of the S wave, are slightly different in time and, if necessary, the slight difference Since compensation is possible, the Q point detection means 80 does not substantially change whether any of the Q point, the R point, and the S point of the electrocardiographic induction waveform is detected. However, since the R wave appears most prominently in the electrocardiographic induction waveform, the highest reliability can be obtained when the R point, which is the maximum value of the R wave, is detected.
[0025]
At time difference calculating means 82, occurrence time difference TD _M between the detected pressure pulse wave by a cuff pulse wave and the pulse-wave sensor 46 which is detected by the cuff pulse wave sensor 70 is calculated. In the above time difference calculating means 82, for example, the rising point or maximum point of the cuff pulse wave and the pressure pulse wave is detected, respectively, it said occurrence time difference TD _M is by generating time difference between between their rising point or maximum point is determined Calculated. FIG. 4 shows a time difference TD _M (= T _M2LP −T _M1LP ) between times T _M1LP and T _{M2LP at} the rising points (minimum points) of the cuff pulse wave and the pressure pulse wave.
[0026]
The rising point estimation means 84 estimates the rising point (time T _DLP ) of the pulse wave in the aorta based on the occurrence time difference TD _M. In the rising point estimation means 84, for example, the rising point (occurrence time T _DLP ) of the pulse wave in the aorta is estimated based on the actual generation time difference TD _M from the relationship (data map or function) stored in advance as shown in Equation 1. Is done. As shown in FIG. 5, L ₁ in Equation 1 is the length of the artery A from the left ventricle of the heart H to the site where the cuff 10 is attached, and L ₂ is the pressure from the site where the cuff 10 is attached. This is the length of the artery to the site where the pulse wave sensor 46 is attached. K ₁ is a correction coefficient for correcting a difference in propagation velocity derived from the diameter and flexibility of the artery including the aorta at the distance L ₁ , and k ₂ is the value of the artery including the aorta at the distance L ₂ . This is a correction coefficient for correcting the difference in propagation speed derived from the diameter and flexibility. The distances L ₁ and L ₂ and the correction coefficients k ₁ and k ₂ are values obtained experimentally in advance, and are set to constant values.
[0027]
[Expression 1]
T _DLP = T _{M1LP -TD M} (k ₁ L ₁ / k ₂ L ₂ )
[0028]
In the precursor discharge period calculation means 86, a precursor discharge period PEP (= T _DLP −T _Q ) that is a period from the point Q of the electrocardiogram waveform (time T _Q ) to the rising point of the pulse wave in the aorta (time T _DLP ). : M sec) is calculated. Then, the evaluation means 88 evaluates the cardiac function based on the precursor emission period PEP and outputs the evaluation result to the display 32. For example, the evaluation means 88 includes a first storage means (not shown) that stores a resting precursor PEP ₁ before an exercise load is applied to the living body by an exercise load apparatus (not shown), and an exercise load on the living body by the exercise load apparatus. And a second storage means (not shown) for storing the precursor discharge period PEP ₂ after the change is given, and a change amount ΔPEP (= PEP ₂ −PEP ₁ ) between the precursor discharge period PEP ₂ and the precursor discharge period PEP ₁ or The cardiac function is evaluated based on whether or not the rate of change R _PEP (PEP ₂ / PEP ₁ ) has exceeded a plurality of predetermined criteria. When there is myocardial ischemia, the function of the myocardium decreases and the precursor period PEP increases. Therefore, it is evaluated that the larger the change amount ΔPEP or the change rate R _PEP is, the lower the cardiac function is. Alternatively, the evaluation means 88 evaluates the cardiac function based on the recovery time or recovery rate at which the precursor delivery period PEP ₂ after the end of the exercise load application recovers toward the resting precursor delivery period PEP ₁ . It is evaluated that the longer the recovery time or the slower the recovery, the lower the cardiac function.
[0029]
6 and 7 are flowcharts for explaining the main part of the control operation of the electronic control device 28. FIG. In step SA1 in FIG. 6 (hereinafter, step is omitted), it is determined whether or not the apparatus has been activated by operating an activation button (not shown). If the determination at SA1 is affirmative, the SA2 precursor emission period measurement routine corresponding to the precursor emission period measuring means 78 is executed as shown in FIG.
[0030]
In SA2-1 of FIG. 7, the electrocardiographic induction wave detected by the electrocardiographic induction device 60, the cuff pulse wave detected by the cuff pulse wave sensor 70, and the pressure pulse wave detected by the pressure pulse wave sensor 46 are predetermined. Each sampling period is read. Next, in SA2-2 corresponding to the Q point detection means 80, it is determined whether or not the Q point of the electrocardiographic induction wave has been detected. If this determination is negative, SA2-1 and subsequent steps are repeatedly executed. However, if the determination of SA2-2 is positive, the occurrence time T _Q of Q points of the ECG wave is stored in SA2-3. This state is shown at time _{TQ in} FIG.
[0031]
Next, in SA2-4, it is determined whether or not the rising point of the cuff pulse wave has been detected. If this determination is negative, SA2-1 and subsequent steps are repeatedly executed. However, when the determination of SA2-4 is affirmed, the generation time T _M1LP of the rising point of the cuff pulse wave is stored in _SA2-5 . This state is shown at time T _{M1LP in} FIG. In subsequent SA2-6, it is determined whether or not the rising point of the pressure pulse wave has been detected. If this determination is negative, SA2-1 and subsequent steps are repeatedly executed. However, if the determination in SA2-6 is affirmed, the generation time T _M2LP of the rising point of the pressure pulse wave is stored in _SA2-7 . This state is shown at time T _{M2LP in} FIG. In _SA2-8 , a time difference TD _M (= T _M2LP −T _M1LP ) between the generation time T _M1LP of the rising point of the cuff pulse wave and the generation time T _M2LP of the rising point of the pressure pulse wave is calculated. In the present embodiment, SA2-4 to SA2-8 correspond to the time difference calculation means 82.
[0032]
Next, in SA2-9 corresponding to the rising point estimation means 84, the pulse wave in the aorta is _calculated based on the actual time difference TD _M and the cuff pulse wave rising point generation time T _M1LP from Equation 1 stored in advance. The rising point occurrence time T _DLP is calculated. Then, the in SA2-10 corresponding to the pre-ejection period calculation unit 86, the occurrence of the rising point of the pulse wave in the aorta estimated in generation time T _Q and SA2-9 of stored Q point at SA2-3 time Based on T _DLP , the precursor delivery period PEP (= T _DLP −T _Q ) is calculated. Initially, since it is at rest before exercise load application, the precursor emission period PEP is stored as PEP ₁ .
[0033]
Returning to FIG. 6, in the subsequent SA3, it is determined whether or not the measurement of the precursor delivery period PEP ₂ after the exercise load is applied is completed. Since the determination of SA3 is initially denied, it is determined in SA4 whether exercise load application has been completed. Since the determination of SA4 is also denied at the beginning, a signal for permitting the operation of the exercise load device (not shown) is output in SA5. As the exercise load device, for example, a well-known treadmill, ergometer, or the like is used, and the exercise load amount is set by a medical worker to a value that enables cardiac function evaluation within a range in which the burden on the living body is not excessive. The
[0034]
Next, whether or not the measurement of the precursor period PEP ₂ after the exercise load is completed is determined by SA3, but the measurement of the precursor period PEP ₂ after the exercise load is not yet completed. Therefore, it is repeatedly determined whether or not the exercise load application has been completed in SA4.
[0035]
When the exercise load application by the exercise load device is completed, the determination of SA4 is affirmed. Therefore, the precursor emission period PEP is measured in the same manner as described above by executing the SA2 precursor emission period measurement routine. . At this time, since the exercise load is applied, the precursor discharge period PEP measured this time is stored as PEP ₂ .
[0036]
Then, in SA6 corresponding to the evaluating means 88, cardiac function is evaluated based on the duration PEP ₁ and PEP ₂ pre-ejection. For example, based on whether or not the rate of change R _PEP (PEP ₂ / PEP ₁ ) between the precursor delivery period PEP ₂ and the precursor delivery period PEP ₁ exceeds a preset judgment criterion value, a plurality of stages of cardiac function And the evaluation result is displayed on the display 32.
[0037]
As described above, according to the present embodiment, the Q point (T _Q ) of the electrocardiographic induction waveform detected by the electrocardiographic induction device 60, the pulse detected by the cuff pulse wave sensor 70 and the pressure pulse wave sensor 46, respectively. Based on the wave detection points (T _M1LP and T _M2LP ), the precursor period PEP ₁ and PEP ₂ from the point Q to the pulse wave rising point T _DLP in the aorta of the heart are measured for the precursor period. as measured by SA2 corresponding to the means 78, by SA6 corresponding to the evaluation means 88, cardiac function is evaluated based on the duration PEP ₁ and PEP ₂ out its precursor. Therefore, since the cardiac function is evaluated based on the precursor generation periods PEP ₁ and PEP ₂ directly related to the ischemic state of the myocardium, an accurate evaluation result of the cardiac function can be obtained.
[0038]
Further, according to the present embodiment, the SA2 corresponding to the precursor ejection period measuring unit 78 measures the precursor ejection periods PEP ₁ and PEP ₂ before and after the exercise load is applied to the living body, and the SA6 corresponding to the evaluation unit 88. Is for evaluating the cardiac function based on the mutual changes of the precursor periods PEP ₁ and PEP ₂ respectively measured by the precursor period measuring means 78. For this reason, since a decrease in myocardial function due to myocardial ischemia appears remarkably when exercise load is applied, evaluation of cardiac function can be obtained more accurately by observing changes in the precursor period.
[0039]
In addition, according to the present embodiment, the pulse wave sensor is attached to two predetermined locations on the living body and detects a pulse wave generated at these two locations, respectively, and a pair of cuff pulse wave sensors 70 and pressure pulse waves. The sensor 46 includes a precursor discharge period measuring unit 78. The generation time difference TD _M (= T _M ) of the cuff pulse wave and the pressure pulse wave detected by the pair of cuff pulse wave sensor 70 and the pressure pulse wave sensor 46, respectively. _M2LP− T _M1LP ), a time difference calculating means 82 for calculating the Q point of the electrocardiogram waveform, a Q point detecting means 80 for substantially detecting the Q point, and a Q point detecting means 80 detected from a preset relationship. it is intended to include a pre-ejection period calculation unit 86 calculates the pre-ejection period PEP, based on the occurrence time difference TD _M of the pulse wave calculated by the the Q point time difference calculating means 82. Thus, the Q point (T _Q) and the cuff pulse wave and pulse wave pre-ejection period PEP, based on the occurrence time difference TD _M of is calculated, the accuracy of the pre-ejection period PEP is increased.
[0040]
Further, according to this embodiment, the pre-ejection period measuring means 78, the rising point estimation for estimating the rising point of the pulse wave of the aorta based on the occurrence time difference TD _M of the pulse wave calculated by the time difference calculating means 82 The precursor discharge period PEP is calculated based on the Q point (T _Q ) detected by the Q point detecting means 80 and the rising point T _DLP of the pulse wave in the aorta estimated by the rising point estimating means 84. Since it is calculated, the precursor ejection period PEP can be calculated more accurately and easily.
[0041]
Further, according to the present embodiment, since the cardiac function evaluation device is provided together with the blood pressure monitoring device 8, there is an advantage that the cuff pulse wave senna 70 including the cuff 10 and the pressure pulse wave sensor 46 can be used together.
[0042]
As mentioned above, although one Example of this invention was described based on drawing, this invention is applied also in another aspect.
[0043]
For example, in the illustrated embodiment, the point Q from the formula 1 (T _Q) and the cuff pulse wave and pulse wave pre-ejection period PEP, based on the occurrence time difference TD _M of has been calculated, obtained in advance From the relationship, the precursor emission period PEP may be calculated based on the actual pulse wave propagation velocity between the cuff pulse wave sensor 70 and the pressure pulse wave sensor 46.
[0044]
When the pulse wave generation time difference TD _A between the left ventricle and the upper arm of the heart can be considered to be substantially constant, the generation time difference TD set in advance from the rising point T _M1LP of the actual cuff pulse wave. The rising point T _DLP of the pulse wave in the aorta may be obtained by subtracting _A. In such a case, there is an advantage that only one pulse wave sensor is used.
[0045]
Considering that the pulse wave velocity changes in relation to the blood pressure value, the correction coefficient k ₁ or k ₂ may be a function of the actual blood pressure value of the living body. In this way, higher accuracy can be obtained.
[0046]
In the above-described embodiment, the cuff pulse wave sensor 70 using the cuff 10 detects the cuff pulse wave generated in the upper arm portion of the living body and is pressed directly above the radial artery of the same arm. Although 46 is described as detecting the pressure pulse wave generated at the wrist, the cuff pulse wave sensor 70 and the pressure pulse wave sensor 46 may be attached to different arms.
[0047]
In the above-described embodiment, the cuff pulse wave sensor 70 using the cuff 10 and the pressure pulse wave sensor 46 pressed from right above the artery are used as the pulse wave sensor. A photoelectric pulse wave sensor comprising a light source and a light detecting element for detecting transmitted light or reflected light of the light emitted from the light source, or an ultrasonic pulse wave sensor for detecting arterial wall vibration using ultrasonic waves Other types of pulse wave sensors may be used. The pulse wave sensor may be attached to any part of the living body as long as a time difference is generated in the detected pulse wave. When the photoelectric pulse wave sensor is used, a cardiac function evaluation device is provided by providing a pulse oximeter including a photoelectric pulse wave sensor that detects a pulse wave using irradiation light of two types of wavelengths. There is an advantage that the pulse wave sensor can also be used.
[0048]
In addition, the present invention can be variously modified without departing from the gist thereof.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a blood pressure monitoring apparatus according to an embodiment of the present invention.
2 is a functional block diagram for explaining a main part of a control function of the electronic control device of the embodiment of FIG. 1; FIG.
FIG. 3 is a diagram illustrating correspondence relationships used in the embodiment of FIG. 1;
4 is a time chart showing an electrocardiographic induction waveform detected by the electrocardiographic induction device of FIG. 1, a cuff pulse wave detected by a cuff pulse wave sensor, and a pressure pulse wave detected by a pressure pulse wave sensor. FIG.
FIG. 5 is a diagram for explaining a calculation formula for a precursor ejection period PEP used in the embodiment of FIG. 1;
6 is a flowchart for explaining a main part of the control operation of the electronic control device of the embodiment of FIG. 1; FIG.
FIG. 7 is a flowchart illustrating a precursor ejection period measurement routine of FIG.
[Explanation of symbols]
46: Pressure pulse wave sensor (pulse wave sensor)
60: ECG induction device 70: Cuff pulse wave sensor (pulse wave sensor)
78: Precursor emission period measurement means 80: Q point detection means 82: Time difference calculation means 84: Rise point estimation means 86: Precursor emission period calculation means 88: Evaluation means

Claims (1)

A cardiac function evaluation apparatus for evaluating the blood ejection function of a living body heart,
An electrocardiographic induction device for detecting the electrocardiographic induction waveform of the living body;
A pair of pulse wave sensors that are mounted at two predetermined locations on the living body and detect pulse waves generated at the two locations;
Estimation and the time difference calculating means for calculating the occurrence time difference of the detected pulse wave, respectively, the rising point of the pulse wave in the aorta based on the occurrence time difference of the pulse wave calculated by said time difference calculating means by said pair of pulse wave sensor Rising point estimating means, Q point detecting means for substantially detecting the Q point of the electrocardiographic induction waveform, and Q point detected by the Q point detecting means and the rising point estimation from a preset relationship And a precursor emission period calculating means for calculating the precursor emission period based on the rising point of the pulse wave estimated by the means, the Q point of the ECG waveform detected by the ECG apparatus and the pulse A precursor for calculating a cardiac precursor period from a point Q of the electrocardiogram-induced waveform to a rising point of the pulse wave in the aorta of the heart based on the pulse wave detection point detected by the wave sensor Measurement period And,
An evaluation means for evaluating the cardiac function of the heart based on the precursor delivery period measured by the precursor delivery period measurement means.

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