JP4505096B2 - Heart rate interval display method and heart rate interval display device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a heartbeat interval display method for displaying a heartbeat interval on a two-dimensional graph based on a biological signal such as an electrocardiogram waveform, and a heartbeat interval display device using the method.
[0002]
[Prior art]
Heart rate (pulse) monitoring method for measuring the heart rate and pulse of the living body from the electrocardiogram waveform and photoelectric pulse wave, and displaying the instantaneous heart rate and its trend graph Devices using that method have existed for some time. As one method, in order to evaluate the enhanced state of the sympathetic nerve and the cardiac vagus nerve, in the two adjacent RR intervals (heart rate intervals), the first RR interval is plotted on the horizontal axis and the next RR interval is plotted vertically. The method of plotting the point to be the coordinate of the axis is repeatedly processed for continuous RR intervals while overlapping one beat at a time (Poincare plot: Therapeutic Research Vol.17 No.1 1996 "Heart rate fluctuation and autonomic nerve" see page 216 ) 7 and 8 illustrate the heart rate interval display method (Poincare plot method) of the RR interval. When an electrocardiographic waveform as shown in FIG. 7 is collected, first, the position of the R wave within each beat is identified by the electrocardiographic waveform. In FIG. 7, the positions are R1, R2, R3, and R4. If the time from R1 to R2 is T21, the time from R2 to R3 is T32, and the time from R3 to R4 is T43, as shown in FIG. 8, the horizontal axis value is T32 and the vertical axis value is T21. Plot at the point. Subsequently, the horizontal axis is plotted at T43 and the vertical axis is plotted at T32. If this process is performed for data of continuous RR intervals, the fluctuation of the heart rate interval is plotted on a two-dimensional graph. If the heartbeat interval is not constant, the plot area on the graph is expanded, and when the heartbeat interval approaches constant, the plot area on the graph is narrowed.
[0003]
In the Poincare plot which is a heartbeat interval plot graph, it is possible to suggest a heart state by a pattern of plots as shown in ac of FIG. FIG. 9a is typical data of a normal person and has a comet-like shape. FIG. 9b shows data of a patient with heart failure. The fluctuation component is smaller than that of FIG. FIG. 9c shows data of a heart failure patient, and the plot pattern is complicated by data in which many arrhythmias appear. (See Therapeutic Research Vol.17 No.1 1996 “Heartbeat fluctuation and autonomic nerve”)
[0004]
It is also known that the degree of heartbeat fluctuation varies with aging, alcohol consumption and smoking, as shown in Therapeutic Research Vol.17 No.1 1996 “Heartbeat fluctuation and autonomic nerve”. Heart rate fluctuations tend to decrease due to aging and the like, whereby the heart rate interval plot distribution (Poincare plot distribution) approaches a straight line of x = y in the graph.
[0005]
[Problems to be solved by the invention]
However, even if the heart rate interval data (Poincare plot) of the measurement subject is displayed and the absolute heart rate fluctuation of the measurement subject can be intuitively grasped, for example, the age of the measurement subject is considered. In this case, there was no clear way to relatively determine the degree of fluctuation of the person being measured compared to the average degree of heartbeat fluctuation of the person being measured.
[0006]
Such problems include not only the parameters of the patient's age, but also the daily consumption and smoking of the patient, trends in the patient's daily life such as regular sports, body fat This also occurs when making a relative determination of heart rate fluctuations of the subject taking into account biological information such as rate, body weight, blood glucose level, urine sugar level, blood pressure value, and lipid metabolism.
[0007]
In view of such a problem, the present invention makes it possible to determine the degree of heartbeat fluctuation more objectively and intuitively. The distribution state of the heartbeat interval plot (Poincare plot) of the subject is It is possible to grasp how the distribution differs from the average target group included.
[0008]
[Means for Solving the Problems]
In order to achieve the above-mentioned object, based on the heart rate information of the person to be measured, on the two-dimensional orthogonal graph where the heart rate interval is x = y , the reference heart rate interval is set as one of the values on the x- axis. Heartbeat interval plot display means for plotting a heartbeat interval before or after the heartbeat interval as a value on the other y- axis on a two-dimensional orthogonal graph, and subject information having a gender button, age button, and confirm button The heart rate interval display device comprises an input unit and a control unit, and has an average heart rate interval plot distribution area storage means for storing an average heart rate interval plot distribution area based on information input with a gender button and an age button. The person-to-be-measured information input unit further includes a dot matrix liquid crystal capable of displaying Chinese characters, and the operation procedure is displayed on the dot matrix liquid crystal capable of displaying Chinese characters. The average heart rate interval plot distribution area is drawn on the dot matrix liquid crystal as an isosceles trapezoidal figure symmetric with respect to the x = y line based on the gender and age information input by the sex button and the age button. Then, control is performed such that the drawing of the heart rate interval plot of the measurement subject measured in real time is superimposed and displayed .
[0009]
Also, what achieves the above-mentioned object is that, based on the heart rate information of the person to be measured, the heart rate interval is a value on one axis on the two-dimensional orthogonal graph, and the reference heart rate interval is A heartbeat interval plot display means for plotting a heartbeat interval before or after one beat as a value on the other axis on a two-dimensional orthogonal graph, an information input means for inputting feature information of the person to be measured, and the feature information Average heart rate interval plot distribution area storing means for storing a plurality of average heart rate interval plot distribution areas based on the information input means, and selectively displaying the corresponding average heart rate interval plot distribution area as the display means. A heartbeat interval display device, characterized by being superimposed on a heartbeat interval plot of a measurement subject.
[0010]
The characteristic information includes gender, age or age, smoking amount, alcohol consumption, body position during measurement, exercise amount or calorie consumption, body fat percentage, body weight, blood glucose level, urine sugar level, blood pressure level, lipid metabolism level. Of these, it is preferable to use one or a combination thereof.
[0011]
Further, it is preferable that the average heartbeat interval plot distribution area storage unit stores a plurality of pieces of point information of the graph as coordinate values and performs a process of connecting the point information with a line when the superimposed display is performed.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the drawings.
[0013]
FIG. 1 is a diagram showing a configuration of a heartbeat interval display device 300 in an embodiment according to the present invention. In FIG. 1, reference numeral 310 denotes a biological electrode that detects a biological signal (electrocardiographic waveform) from the measurement subject 100. It is assumed that it is composed of electrode materials such as conventional electrocardiographs such as silver, silver chloride and carbon.
[0014]
The measurement is started by pressing a measurement start switch (not shown). Before the measurement, the biological electrode 310 is in contact with the measurement subject 100, and the electrocardiographic waveform is collected from the biological electrode at the same time as the measurement is started. It shall be possible. Note that the measurement may be ended by pressing a measurement end button (not shown), or may be automatically ended after a predetermined time has elapsed after the measurement start switch is pressed. Further, it is possible to check whether or not the biological electrode has been detached from the measurement subject, and the measurement may be terminated when the electrode has been detached and a certain time has passed.
[0015]
First, when the measurement is started, the control unit 350 performs processing for initializing information in the heartbeat interval storage unit 360.
[0016]
The electrocardiographic signal from the living body detected by the living body electrode 310 is weak for direct analysis, and therefore is amplified by the amplifier 320 and sent to the heartbeat detecting unit 330. The heartbeat detection unit 330 is configured by a digital filter or the like, and performs appropriate bandpass processing for detecting the RR interval in the electrocardiogram waveform together with a removal filter such as noise and a baseline fluctuation component of the waveform.
[0017]
The signal processed by the heartbeat detection unit 330 is then sent to the heartbeat interval detection unit 340. The heartbeat interval detection unit has a timekeeping function for detecting the heartbeat interval, performs threshold detection of the signal from the heartbeat detection unit 330, stores the time when the threshold is exceeded using the timekeeping function, Next, a time interval that falls below the threshold and exceeds the threshold again is output to the control unit 350 as a heartbeat interval.
[0018]
FIG. 2 shows an example of data processing for outputting the waveform output from the amplifier 320 as heartbeat interval data to the control unit. In FIG. 2, reference numeral 410 denotes an electrocardiographic waveform output from the amplifier 320, and in many cases, baseline fluctuations and high-frequency noise are superimposed. Basically, baseline fluctuations pass through a high-pass filter, and high-frequency noise passes through a low-pass filter, resulting in a signal from which noise components such as 420 are removed. An R wave of an electrocardiogram waveform can be extracted by passing through a band pass filter centering around 17 Hz, and this process converts the 420 waveform into a 430 waveform. A threshold is set for the waveform 430 (level indicated by a wavy line in the figure), and the time (msec unit) when the threshold is exceeded is stored (t1 in the figure). Thereafter, the time at which the threshold value is exceeded and the threshold value is exceeded again is stored (t2 in the figure), and the interval (t2-t1) between these two times is output as the heartbeat interval. At this time, the data of t1 becomes unnecessary, and may be cleared from the stored information. Next, the time at which the threshold value was exceeded after being below the threshold value is stored again (t3 in the figure), and the interval (t3-t2) from time t2 at which the threshold value was previously exceeded is output as the next heartbeat interval.
[0019]
Thus, it becomes possible to output heartbeat interval data from the signals sequentially obtained from the amplifier. In the present embodiment, the filter portion for heart rate detection and heart rate interval detection is shown as a digital circuit. However, the same result can be obtained even if a signal processing algorithm is programmed and processed as software using a microcomputer or the like. It is also possible to configure some functions as a circuit and control the remaining parts by software.
[0020]
Heartbeat interval data detected by the heartbeat interval detector 340 is sequentially sent to the controller 350. The control unit 350 stores the heart rate interval data sequentially sent from the heart rate interval detection unit 340 based on the format defined in the heart rate interval storage unit 360.
The heart rate interval is preferably plotted and displayed in real time using the method as described above.
[0021]
The control unit prompts the measurement subject information input unit 370 to input measurement subject information before starting the measurement.
[0022]
FIG. 3 shows an example of the measurement subject information input unit. In FIG. 3, 510 is a dot matrix liquid crystal capable of displaying Kanji characters, 520 is a gender 1 button to be pressed when inputting gender information of the measurement subject, and 530 is a gender 2 button to be pressed when inputting a woman as well. 540 is the age 1 button to be pressed when inputting information that the age of the person to be measured is 20 years old or less, 550 is also the age 2 button to be pressed when inputting information about 21 to 30 years old, 560 is 31 similarly Age 3 button for inputting information about -50 years old, 570 is the age 4 button to be pressed when inputting information about 51 years of age or more, 580 is the information about the gender and age of the person to be measured after each button is pressed The confirmation button 590 to be pressed when confirming 590 is an interruption button to be pressed when the determination of the gender and age of the measurement subject is interrupted.
[0023]
When a signal for prompting information input of the measurement subject is input from the control unit 350 to the measurement subject information input unit 370, the measurement subject information input unit 370 displays “gender (male / female) of the measurement subject” in the dot matrix liquid crystal 510. Please press the button. ”Is displayed and the operation of the operator is awaited. If the person to be measured is a 45-year-old male, the operator presses the gender 1 button 520. When a signal indicating that either the gender 1 button 520 or the gender 2 button 530 is pressed is input, “Please press the button of the person to be measured” is displayed on the dot matrix liquid crystal 510 and the operator again. Wait for operation. In this example, the operator presses the age 3 button 560.
[0024]
When the gender confirmation information and the age confirmation information are input, “Please press the confirmation button” is displayed on the dot matrix liquid crystal 510. At this time, if the information of the sex and age simultaneously pressed are displayed together on the dot matrix liquid crystal 510, an erroneous input by the operator can be prevented. In this example, the dot matrix liquid crystal 510 is “31 to 50 years old male. Please press the confirm button if you like”.
[0025]
When the input of information is interrupted, the interrupt button 590 may be pressed.
[0026]
In the above example, the input is confirmed using the dot matrix liquid crystal, but it is also possible to use a gender / age button as a membrane switch or the like incorporating an LED. LEDs are incorporated into all six buttons, the gender button and the age button, and the LED of the six buttons disappears when a signal is input from the control unit 350 to the subject information input unit 370 to prompt the subject to enter information. Shall be in a state. If the Gender 1 button is pressed in this state, the LED incorporated in the Gender 1 button will be lit. If the Gender 2 button is pressed in this state, the Gender 1 button LED will disappear and be incorporated in the Gender 2 button. The LED of the button that was newly pressed with the gender 1 button and the gender 2 button is lit, and the LED of the button that is not is turned off so that the LED is lit. Such an operation makes it possible to reduce erroneous input of the operation. In the age buttons, it is also possible to turn on only the most recently pressed LED among a plurality of age buttons and turn off the LEDs of the other buttons.
[0027]
As described above, when the signal for prompting the subject to input information is input from the control unit 350 to the subject information input unit 370, the above-described operation is performed, and finally the subject information input unit. In 370, the signal input to the confirmation button 580 or the interruption button 590 is returned to the control unit 350. When the enter button 580 is input, the information about the pressed gender and age button is also returned to the control unit 350.
[0028]
When the subject information input is confirmed, if the target isosceles trapezoid is drawn on the x = y straight line as shown in FIG. 4 on the heart rate interval plot graph (Poincare plot graph), the heart rate of the subject is measured. It is possible to grasp how the distribution state of the interval plot graph (Poincare plot) differs from the distribution of the average graph plot target group including the person to be measured. The isosceles trapezoid shown in Fig. 4 is considered to be the outline of the distribution region of the average heart rate interval plot (Poincare plot) of the gender and age that includes the subject, and the heart rate interval plot (Paincare) distribution of the subject is If it protrudes outside the figure of an isosceles trapezoid, it indicates that the subject's heart rate fluctuation is larger than the average distribution of the same family name and age.
[0029]
Conversely, if the subject's heartbeat interval plot (Poincare plot) distribution is distributed substantially inside the isosceles trapezoid figure, the subject is compared to the average distribution of the same family name and age. If the subject's Poincare plot distribution almost matches the outline of the isosceles trapezoid, the heart rate fluctuation of the subject is almost equal to the average heart rate fluctuation of the same family name and age. Equivalent and intuitive judgment is possible. In order to draw such an isosceles trapezoid, it is only necessary to determine the coordinates of two points as shown in FIG. In FIG. 4, (x1, y1) to (x2, y2), (x2, y2) to (y2, x2), (y2, x2) to (y1, x1), (y1, x1) to (x1 , y1), an isosceles trapezoid can be drawn by drawing four straight lines.
[0030]
In this embodiment, an isosceles trapezoid is used as an outline indicating an average distribution, but it is possible to express a shape close to a general heartbeat interval plot (Poincare plot) from more point data, It is also possible to approximate a triangle formed by a point at the target position of x = y from the coordinates of only one point and three points of the origin to a general heartbeat interval plot (outline of Poincare plot).
[0031]
If one point of the heart rate interval plot graph (Poincare plot graph) is indicated by 4 bytes (X coordinate 2 bytes, Y coordinate 2 bytes), in this embodiment, it is only necessary to determine the coordinates of 2 points for each gender and age. In order to draw the outline data in the case of, the average heart rate interval plot (Poincare plot) distribution region is memorized when there are 4 types by age and 2 types by sex as shown in FIG. The data storage unit (average heart rate interval graph plot storage unit) 380 may have a memory capacity of 8 × 2 × 4 = 64 bytes.
[0032]
In the reference data storage unit, the x1 value of the outline shape of the average heart rate interval plot (Poincare plot) for males and under 20 in the 2 bytes from address 0 to address 1 is also y1 from address 2 to address 3. The same x2 value is stored in addresses 4 to 5 and y2 is stored in addresses 6 to 7, and the average Poincare for men and 21 to 30 years old is in the same format. The outline data of the plot is male at 31-23, 31-50 years old, male at 24-31, male over 51, female at 32-39, female under 20 years old, female at 40-47, 21 It is assumed that 30-year-old, 48-55 address female, 31-50 years old, 56-63 address female-51-year-old outline shape data.
[0033]
Based on the signal from the person-to-be-measured person information input unit 370, the control unit 350 reads out data from the address where the corresponding sex / age is stored in the reference data storage unit 380 having the above-described data storage format configuration, and outputs the output unit 390. A command is issued to draw an isosceles trapezoid as shown in FIG.
[0034]
FIG. 5 shows a flowchart until the output unit draws the outline shape based on the information from the measurement subject information input unit.
[0035]
First, when information is input from the measurement subject information input unit (S710), it is determined whether the information is an interrupt button signal (S720). If the information is an interrupt button signal, the process is performed without drawing the outline shape. If it is not an interrupt button signal (if it is a confirm button signal), the gender and age information sent together with the confirm button signal is read (S730). Among the read information, when the gender information is 0, it indicates a male, when it is 1, it indicates a female. When the age information is 0, it is 20 years old or younger. ~ 50 years old, 3 indicates 51 years old or older, and the coordinates (x1, y2) and (x2, y2) data for drawing the isosceles trapezoid outline shape are
x1: [sex information] x 32 + [age information] x 8
y1: [sex information] x 32 + [age information] x 8 + 2
x2: [sex information] x 32 + [age information] x 8 + 4
y2: From the [sex information] × 32 + [age information] × 8 + 6 addresses, each is read as numerical data of 2 bytes. In this way, the coordinate data of two points is read (S740), a straight line is drawn from the coordinates (x1, y1) to (x2, y2) (S750), and the coordinates (x2, y2) to (y2, x2) Draw a straight line (S760), draw a straight line from coordinates (y2, x2) to (y1, x1) (S770), draw a straight line from coordinates (y1, x1) to (x1, y1) (S780), The process ends.
[0036]
After drawing such average heart rate interval plot (Poincare plot) outline information for each gender and each age, it is possible to display the heart rate interval in real time, and it is stored in the heart rate interval storage unit 360. A heartbeat interval plot (Poincare plot) is drawn from the heartbeat interval data of the measurement subject, and the two drawings may be superimposed.
[0037]
In FIG. 6, heart rate interval data is configured in a 2-byte integer type in msec units, and is stored in order from address 0 in the heart rate interval storage unit, and there is no measurement data after the address where 0 is stored. The flow of the drawing process to the output part in a control part in case data is memorize | stored in the heartbeat interval memory | storage part by the structure is shown.
[0038]
In the figure, processing is started. First, 2-byte integer type data is read from address 0 of the heartbeat interval storage unit and assigned to variable a (S810). Next, if the variable a is 0, since the heartbeat interval data is not stored in the heartbeat interval storage unit, a determination process for stopping the drawing process is performed (S820).
[0039]
Since the variable a is data in msec units, it is necessary to perform processing for conversion to the scale of the output unit in order to perform drawing processing. For example, if the output unit has a resolution of 1024 dots in length and width, all the areas are Poincare plots, all the information such as axes and scales are not drawn, the minimum display value in the output unit is 200 msec, and the maximum display value is 2000 msec In order to convert msec unit data (variable a) stored in the heartbeat interval storage unit into dot unit data (variable y) corresponding to this output unit,
y = (a-200) / 1800 x 1024
And it is sufficient.
[0040]
The a read in s810 is converted into dot unit data using the above conversion formula (s830). Subsequently, a variable i which is the number of data read is initialized (S840). i is sequentially incremented by 1 (incremented) (S850), and 2-byte integer type data is read from address 2i of the heartbeat interval storage unit and assigned to variable a (S860). If the substituted variable a is 0, the heartbeat interval data is not stored in the heartbeat interval storage unit, so a determination process for stopping the drawing process is performed (S870). Using the same conversion formula as that used to convert a to variable y, the data is converted to dot data (s880). Note that the data in this case is a variable x. Subsequently, a process of plotting on the two-dimensional coordinates (x, y) using the values of the variable x and the variable y obtained in the series of processes is performed on the output unit 390 (s890).
[0041]
In order to process a new plot, variable x is assigned to variable y (s891), and the process returns to (s850).
[0042]
By performing this process, a drawing command for each heartbeat interval plot (Poincare plot) is sequentially sent from the control unit to the output unit.
[0043]
In the output unit, a vertical and horizontal liquid crystal of 1024 × 1024 dots may be used as a display portion, and a point plot or straight line drawing command may be received from the control unit and displayed on the liquid crystal display unit.
[0044]
Note that the output unit is not limited to the liquid crystal, and may be another display device such as a CRT, or an output device for paper such as a printer or a plotter. For example, when a printer or the like is used, a personal computer can be used as the control unit, and a drawing command to the output unit can be simply realized as a command to a general printer driver.
[0045]
In this embodiment, first, gender / age information input, average heart rate interval plot (Poincare plot) outline drawing is performed, then signal measurement from the bioelectrode is started, and the heart rate interval is measured in real time. Although the measurement procedure is performed every time the measurement subject's heartbeat interval plot (Poincare plot) is drawn until the measurement is completed, the order of the processing is not limited to this in the present invention.
[0046]
For example, measuring the signal from the bioelectrode, measuring and sequentially storing the heart rate interval data, inputting the measured person information of gender and age after completing the signal measurement, and drawing the average heart rate interval plot (Poincare plot) outline Then, the heartbeat interval plot (Poincare plot) of the measurement subject stored on the screen may be drawn.
[0047]
In this embodiment, gender / age was used as a comparative classification of subjects, but trends in daily life of subjects such as alcohol consumption / smoking amount and regular sports, body fat percentage / weight, etc. It is also possible to display similar comparative classification parameters (average heartbeat interval plot outline) by inputting biological information such as blood glucose level, urine sugar level, blood pressure value, and lipid metabolism.
[0048]
【The invention's effect】
As described above, according to the heartbeat interval display method and the heartbeat interval display device of the present invention, the heartbeat interval plot (Poincare plot) display based on the average reference data area applicable to the subject and the heartbeat interval information of the subject can be performed. Since it is displayed in a superimposed manner, it is possible to easily grasp the state of the heart from the fluctuation component of the heartbeat.
[0049]
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a heartbeat interval display device of the present invention.
FIG. 2 is a diagram showing a processing example of waveform data output from heartbeat measurement in the heartbeat interval display device of the present invention.
FIG. 3 is a diagram showing an example of a display unit of the heartbeat interval display device of the present invention.
FIG. 4 is an average view of data groups to which a person to be measured belongs based on a feature that makes it possible to classify a general collection data group and a collection data group of a person to be measured in the heartbeat interval display device of the present invention; It is a figure which shows a graph plot distribution area | region.
FIG. 5 is a flowchart until the output unit draws an outline shape based on information from the measurement subject information input unit. FIG. 6 is a flowchart showing a drawing process on the output unit in the control unit. It is.
FIG. 7 is a diagram showing a heart rate interval plot (Poincare plot) method of RR intervals.
FIG. 8 is a diagram for explaining a heartbeat interval plot (Poincare plot);
FIG. 9 is a diagram showing a plot pattern of a heartbeat interval plot (Poincare plot).
[Brief description of symbols]
100 Measurement Person 300 Heartbeat Monitor 310 Electrode Unit 320 Amplifier 330 Heartbeat Detection Unit 340 Heartbeat Interval Detection Unit 350 Control Unit 360 Storage Unit 370 Display Unit 380 Start Switch 600 Average Heart Rate Interval Plot (Poincare Plot) Area

Claims (2)

Based on the heart rate information of the person to be measured, on the two-dimensional orthogonal graph where the heart rate interval is x = y , the reference heart rate interval is set to one of the values on the x axis, and one beat before the reference heart rate interval or Heart rate interval plot display means for plotting a later heart rate interval as a value on the other y- axis on a two-dimensional orthogonal graph , a subject information input unit having a gender button, an age button, and a confirmation button, a control unit, With
A heart rate interval display device comprising: an average heart rate interval plot distribution area storing means for storing an average heart rate interval plot distribution area based on information input by the gender button and the age button ,
The measurement subject information input unit further comprises a dot matrix liquid crystal capable of displaying kanji,
The operation procedure is displayed by the dot matrix liquid crystal capable of displaying the kanji,
The average heart rate interval plot distribution region is set to the dot matrix liquid crystal on the dot matrix liquid crystal based on the gender and age information input by the control unit using the sex button and the age button. A heartbeat interval display device, wherein the heartbeat interval display device is controlled to superimpose and display the drawing of the heartbeat interval plot of the measurement subject measured in real time . In addition to gender and age information, the information includes smoking amount, alcohol consumption, body position during measurement, exercise amount or calorie consumption, body fat percentage, body weight, blood glucose level, urine sugar level, blood pressure level, lipid metabolism level. The heartbeat interval display device according to claim 1, wherein one of them or a combination thereof is used.

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