JP2006198403A - Heart rate variability analyzing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To quickly perform a role as an alarm reference index of a physiological condition by making a heart rate variability analysis more convenient. <P>SOLUTION: This heart rate variability analyzing device comprises a body; two detecting electrodes for acquiring a subject's ECG signals; an analog signal processing module electrically connected to the detecting electrodes to amplify and filter the ECG signals; an analog to digital conversion unit disposed in the body to convert the ECG signals of analog form from the analog signal processing module, into ECG signals of digital form; a digital signal processing module including a CPU for analyzing heart rate variability on the ECG signals to acquire at least one heart rate variability parameter; a display unit electrically connected to the digital signal processing module and disposed at the body to display the heart rate variability parameter; and a power supply module. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an apparatus for analyzing physiological signals, and more specifically, a central processing unit (CPU) for calculating parameters relating to HRV as well as for recording an electrocardiogram (ECG) signal of a subject. The present invention relates to a device for analyzing heart rate variability (HRV), which has a heart rate variability analysis module.

Recent studies have reported that heart rate variability is a useful indicator of the probability of sudden death, and according to the results of Non-Patent Documents 1 and 2, a decrease in heart rate variability is particularly correlated with an increase in sudden death. . Heart rate variability may reflect the effects of the heart and the autonomic nervous regulation mechanism, and the heart rate variability is compared when the heart and autonomic regulation mechanisms are normal and the heart rhythm can be adjusted to the general condition in a timely manner Although large, the heart rate variability is relatively small when the action of the heart is abnormal or when the autonomic regulation mechanism cannot respond to the general condition in a timely manner. Therefore, although the exact cause of sudden death is unknown, heart rate variability is a very important reference index, as is heart disease, coronary artery disease, arrhythmia, ventricular fibrillation and the like. Heart rate variability is a socio-medical term used in Japan to describe the steadily increasing sudden death phenomenon resulting from excessive physiological and psychological pressure at work. significant. Research shows that people who have spent a long time under stressful labor conditions have lower heart rate variability and are more likely to die suddenly than those who work normally.
Huikuri HV et al. (1992) Sasaki T. Et al. (1999)

  The European Cardiology Association and the North American Pacing and Electrophysiology Society have published reports on heart rate variability measurement and analysis standards, but in practical applications, electrocardiogram (ECG) signal measurement and heart rate variability analysis are performed separately. Is done. On the market, the most relevant product for analyzing heart rate variability is in the form of an analysis package. A conventional method for analyzing heart rate variability first obtains a subject's ECG signal, and then transmits the signal to a computer for computation to obtain a heart rate variability analysis result. Although signal transmission is fast and convenient with today's technology and automatic signal transmission is not difficult, ECG measurements involve the use of electrodes and the HRV analysis interface needs to be performed after the signal is transmitted to the computer. However, the interface is unfamiliar to ordinary people and is not convenient. Therefore, although heart rate variability is a very good indicator for assessing the patient's physiological state, including the autonomic nervous system and the risk of sudden death, such knowledge is difficult to understand and is mainly used for research, clinical diagnosis, etc. Used in range.

SUMMARY OF THE INVENTION An object of the present invention is to provide a heart rate variability analyzer, which includes built-in electrodes and a CPU incorporating a heart rate variability module, and after recording a signal, Heart rate variability analysis can be performed.

  A physiological alarm device that analyzes the heart rate by utilizing a built-in HRV analysis module to inform the subject about his / her physical condition and to be able to adjust his work and rest It is another object of the present invention to provide.

  To achieve this objective, the present invention, which integrates a micro electrical signal detection technique with a signal processing technique, uses two electrodes to measure a signal and a CPU to perform an algorithm and analysis for HRV. Collaborate with. In this way, the present invention not only records ECG signals, but also provides HRV analysis parameters. In addition, it is easy to operate the device of the present invention, so that the subject can understand his / her health condition and pay careful attention to adjust work and rest. The inventive apparatus completes signal acquisition and HRV analysis simultaneously.

  Other additional features, advantages and advantages of the present invention will become apparent from the following description taken in conjunction with the following drawings. The foregoing general description and the following detailed description are exemplary and explanatory, but are not restrictive of the invention. The accompanying drawings are incorporated in and constitute a part of this application and, together with the detailed description, serve to generally explain the tenis of the present invention. Throughout this disclosure, like numerals refer to like parts.

  HRV calculation methods and processes have been organized by the European Heart Association and the North American Pacing and Electrophysiology Society. Since then, the algorithmic principles of HRV analysis in different companies and products have been almost identical. With reference to FIGS. 1 and 2, the procedure for HRV analysis published by the European Heart Society and the North American Pacing and Electrophysiology Society is generally described. In the HRV analysis, the first step (S10) is a step of recording an ECG signal, and the recording time of the ECG signal may be 5 minutes, 12 hours, 24 hours, etc. depending on the necessity of the subject. Clinically, 5 minutes is commonly used as a basic analysis section, and the recording time of ECG signals exceeding 5 minutes is considered more meaningful in analyzing heart rate variability. The next step (S20) is a step of converting the ECG signal into a digital format, followed by a step of detecting an R wave (S30). Usually, the R wave is the maximum peak in the ECG signal, as indicated by # in FIG. After detecting the R wave, the heart rate analysis procedure enters the step of calculating the RR interval (S40). The RR interval is an interval of each heartbeat, and after all R waves are labeled, a sequence of RR intervals is formed. The next step (50) is a step of rejecting irregular RR intervals. As shown in FIG. 3, if the subject has an irregular heart rhythm, the patient has a heart rate interval variation greater than that of a person with regular heart rhythm, and the calculated HRV Does not accurately reflect the heart condition of the subject because it will be greater than the HRV calculated from a person with regular heart rhythm. Therefore, either the standard deviation method that discards RR intervals that exceed 1 or 3 times the standard deviation from the average value of RR intervals, or the average method that averages the previous RR interval or the subsequent RR interval and the irregular RR interval? Irregular RR intervals need to be removed by some mathematical method such as After rejecting the irregular RR interval, the procedure enters a step (S60) of obtaining a regular heart rate interval of NN interval series. At this time, the NN interval series is processed by the time domain HRV analysis, and the time domain HRV analysis is performed by, for example, the median value of the heartbeat interval, the standard deviation or the coefficient of variation, and the root mean square of the successive differences. of success differential) and the like (S70). Alternatively, the procedure may enter the step (S80) of equally spaced sampling using interpolation computation for frequency domain HRV analysis. Since the sampling frequencies of the R waves are not all the same in step (30), the NN interval sequence is converted into a continuous signal by interpolation calculation, sampled at equal intervals, Fourier transform, Hilbert transform, etc. One must proceed to a step (S90) of performing a frequency domain HRV analysis such as the like. After converting the signal from the time domain to the frequency domain and calculating the high frequency power, low frequency power and total power, the procedure includes frequency domain analysis parameters such as HF, LF, LF / HF, LF / TH. Obtainable.

  HRV analysis is very useful in accessing the regulatory mechanisms of the autonomic nervous system, but HRV analysis is not so extensive because HRV analysis is still mainly performed by a computer interface and the recording of ECG signals is complex. Not applied. In order to make HRV analysis more convenient and to quickly serve as an alarm reference indicator for physiological conditions, the present invention provides an HRV analyzer, which can provide an HRV parameter instantaneously. In addition to having the functions of signal measurement and HRV analysis, it is easy to operate.

  Referring to FIG. 4, the present invention includes two sensing electrodes 10, 10 ′, an analog signal processing module 20, an analog-to-digital conversion unit 30, a digital signal processing module 40 for HRV analysis, and a display. A unit 50 and a power supply module 60 are included, and the detection electrodes 10 and 10 'are in contact with the body of the subject to record ECG signals, and the analog signal processing module 20 is used for signal amplification, filtering, and the like. An analog-to-digital conversion unit connected to the sensing electrodes 10, 10 ′ for processing the ECG signal is used to convert the analog ECG processed by the analog signal processing module 20 into a signal digital ECG signal. The display unit 50 is an LCD, LED or the like. In order to display the calculated HRV parameters on the screen, the power supply module 60 is electrically connected to all the modules and units described above to supply power to the device, and the battery set ( cell set) or an external power source. The CPU 42 is a digital signal processing module 40 for processing HRV analysis such as steps (30) to (70) and steps (30) to (90) so as to obtain at least one HRV parameter. It is arranged in the inside. The HRV parameter may be a result of time domain analysis or frequency domain analysis.

  In the present invention, the CPU 42 of the digital signal processing module 40 is electrically connected to the storage unit 44 and the data transmission module 70. A storage unit 44 can store the digital ECG signal and HRV parameters. The data transmission module 70 can transmit data including the digital ECG signal and the HRV parameters stored in the storage unit 44 to the external digital information device 72. The data transmission module 70 includes a USB interface, a Bluetooth interface, an infrared interface, A modem or the like can be used, and the external digital information device 72 may be a personal computer, a PDA, a mobile phone, a database, or the like. The HRV analyzer of the present invention has an operation unit 80 that is electrically connected to the CPU 42, and allows the subject to control the operation of the digital signal processing module 40. The operation unit 80 executes a measurement function, adds / deletes / transmits data in the storage unit 44, inputs personal information of the subject, and sets a date. , Buttons, knobs, touch panels, etc., may be provided in any way.

  Referring to FIG. 5, which is an embodiment of the present invention, the HRV analyzer is a main body 100 (not shown in FIG. 5) having two operation surfaces 102, 102 ′, which defines an internal space. . The detection electrodes 10 and 10 ′ are separately arranged on the left and right sides of the operation surface 102. The analog signal processing module 20, the analog-to-digital conversion unit 30, the digital signal processing module 40 including the CPU 42, and the storage unit 44 are accommodated in the space. The display unit 50 and the operation unit 80 are also disposed on the operation surface 102. The data transmission module 70 is disposed on the other operation surface 102 '.

  In the present invention, the subject can record the lead IECG signal of the subject only by placing the finger of the left hand and the finger of the right hand on the detection electrodes 10, 10 '. In the signal processing procedure, an analog signal processing module 20 electrically connected to the sensing electrodes 10, 10 ′ amplifies and filters the lead I ECG signal and converts the ECG signal from an analog to digital conversion unit 30. Send to. The analog-to-digital conversion unit 30 converts the analog ECG signal into a digital signal and sends the digital signal to the digital signal processing module 40 for analyzing HRV. The CPU 42 of the digital signal processing module 40 includes an HRV analysis program module for executing steps (S30) to (S70) or steps (S30) to (S70) for the ECG signal, and includes a time domain and a frequency domain. HRV parameters of These HRV parameters and ECG signals can be stored in the storage unit 44 and can be simultaneously displayed on the display unit arranged on the operation surface 102. Therefore, the subject can know whether the HRV result of his / her body has reached the warning target.

  Further, the HRV analyzer can be connected to the external information device 72 via the data transmission module 70 arranged on the operation surface 102 ′ in order to transmit the data in the storage unit 44 to the external information device 72. The data transmission module 70 is not limited to any type, and may be, for example, a USB interface, a Bluetooth interface, an infrared interface, a modem, or the like regardless of a wired or wireless system. On the other hand, all functions of the HRV analyzer such as power activation, power off, date setting, subject personal information input, data reading / deleting / transferring in the storage unit 44, etc. are provided on the operation surface 102. It can be easily operated through the arranged operation unit 80.

  There are two external signal sensing electrodes 120, 120 'designed to replace the sensing electrodes 10, 10' for ECG signal measurement. As shown in FIG. 5, the external signal sensing electrodes 120, 120 ′ measure the ECG signal whenever the subject is not feeling well enough not to place his hand on the sensing electrodes 10, 10 ′. And is connected to the main body 100 via the electrode matching port 130 for transmission. After acquiring the ECG signal from the external signal detection electrodes 120, 120 ', the HVR analyzer transmits the ECG signal to the analog-to-digital conversion unit 30 in order to perform the same processing as described above. The external signal detection electrodes 120 and 120 ′ are used to adhere to the body surface of the subject, and in order to record the ECG signals of different leads required by the subject, the lead I according to the adhesion site vector is used. II, III ECG signals can be measured.

  Although the present invention has been disclosed and illustrated with reference to specific embodiments, the principles involved can be used in many other embodiments that will be apparent to those skilled in the art. Accordingly, the invention should be limited only as indicated by the appended claims.

Schematic of ECG signal of heart with normal rhythm. HRV analysis flow chart. The schematic diagram of an ECG signal of arrhythmia. 1 is a block diagram of an embodiment of the present invention. The perspective view of the structure of the embodiment of this invention.

Explanation of symbols

10, 10 ′ detection electrode 20 analog signal processing module 30 digital conversion unit 40 digital signal processing module for HRV analysis 42 CPU
44 Storage Unit 50 Display Unit 60 Power Supply Module 70 Data Transmission Module 72 External Digital Information Device 80 Operation Unit 100 Main Body 102 Operation Surface 120, 120 ′ External Signal Detection Electrode 130 Electrode Compatible Port

Claims (8)

The body,
Two detection electrodes disposed on the main body for obtaining an ECG signal of the subject;
An analog signal processing module disposed within the body and electrically connected to the sensing electrode for amplifying and filtering the ECG signal;
An analog to digital conversion unit disposed in the body for converting the analog ECG signal from the analog signal processing module into a digital ECG signal;
A digital signal processing module disposed within the body, including a CPU for analyzing heart rate variability for the ECG signal to obtain at least one heart rate variability parameter;
A display unit electrically connected to the digital signal processing module and disposed on the body for displaying the heart rate variability parameters;
An apparatus for analyzing heart rate variability, comprising: a power supply module that supplies power to all the above components.   The apparatus according to claim 1, wherein the sensing electrode contacts a left finger and a right finger of the subject, respectively, in order to obtain the lead IECG signal of the subject.   The apparatus of claim 1, wherein the digital signal processing module includes a storage unit connected to the CPU for storing the digital ECG signal and heart rate variability parameters.   The main body includes a data transmission module, and the data transmission module is disposed in the main body and is connected to the CPU for transmitting the ECG signal and the heart rate variability parameter stored in the storage unit to an external digital information device. The apparatus according to claim 3, wherein the CPU is electrically connected to an operation unit disposed in the main body so that the subject can set and control the operation of the analyzer.   The analog signal processing module is electrically connected to an electrode compatible port, the electrode compatible port is disposed in the body and connected to an external signal detection electrode, and the external signal detection electrode is used to acquire the ECG signal. The apparatus of claim 1, wherein the apparatus is a substitute for the sensing electrode. Two sensing electrodes for obtaining an ECG signal of the subject in contact with the body surface of the subject;
An analog signal processing module that is electrically connected to the sensing electrode and performs amplification and filtering of the ECG signal;
An analog to digital conversion unit for converting the analog ECG signal from the analog signal processing module into a digital ECG signal;
A digital signal processing module including a CPU for analyzing heart rate variability for the ECG signal to obtain at least one heart rate variability parameter;
A heart rate variability analyzer, comprising: a display unit electrically connected to the digital signal processing module and displaying the heart rate variability parameter.   7. The apparatus of claim 6, wherein the digital signal processing module includes a storage unit connected to the CPU for storing the digital ECG signal and heart rate variability parameters.   The CPU is electrically connected to a data transmission module for transmitting the ECG signal and the heart rate variability parameter stored in the storage unit to an external digital information device, and the CPU is connected to the analysis by the subject. 8. The device according to claim 7, wherein the device is also electrically connected to an operating unit to allow setting and control of the operation of the device.

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