RU2744967C2 - Heart function determination method, system and electronic device for its implementation - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: inventions group relates to medicine, namely to a method and a system for heart function determination. When executing the method, two streams of laser radiation are formed. Each stream includes radiation from two sources with different wavelengths and different polarizations. Irradiate with streams of tissue from two different parts of the human body. These radiation streams reflected from tissues are converted into electrical signals carrying information about the heart function. Synchronization of mentioned electrical signals is provided. On the basis of these signals, heart electrical forces are determined. The system contains the first and second devices to measure the heart function parameters. Devices are designed to be installed on various parts of the human body. Each device contains a casing. A power source, two sources of laser radiation with different wavelengths and different polarizations, a memory unit for recording information about the heart function, a unit for transmitting information about the heart function parameters are installed into the casing. Each laser source is equipped with a tool to convert laser radiation into electrical signals that carry information about the heart function parameters. In this case, the system provides synchronization of the received electrical signals.

EFFECT: due to the use of laser sources with different wavelengths and different polarizations, an increase in the accuracy of determining the FF waves, segments and intervals reconstructed from electrical signals that carry information about the heart function parameters of the person, obtained from the converted radiation streams, is achieved for a long time in the course of his normal life, simultaneous recording of the cardiographic response from tissues with different sensitivity to the length or polarization of laser radiation.

12 cl, 6 dwg

Description

The technical field to which the invention relates

The invention relates to measuring equipment, in particular to wearable optoelectronic devices for measuring the parameters of the heart and can be used to obtain information about changes in the biopotentials of the human heart.

State of the art

A large number of means for measuring the biopotentials of the human heart is known from the prior art.

As the closest analogue, a well-known device for measuring the parameters of the heart is selected, comprising a housing, a power source installed inside the said housing, a laser radiation source equipped with a means for converting laser radiation into an electrical signal (CN102894965, published on January 30, 2013). This known agent has insufficient sensitivity and accuracy in determining the biopotentials of the human heart.

The essence of the invention

The problem solved by the invention: ensuring monitoring of the work of the heart and measuring the parameters of human cardiac activity.

In the course of solving the problem, the following technical results are achieved: increasing the accuracy of determining the teeth, segments and intervals of a person's cardiogram for a long time in the course of his normal life; simultaneous recording of the cardiographic response from tissues with different sensitivity to the length and / or polarization of laser radiation; ensuring the possibility of integrating the device into information systems based on cloud storage of information.

The above technical results are achieved in that the method for determining the parameters of the heart is that at least two streams of laser radiation are formed, each of which includes radiation from at least two sources with different wavelengths, these streams are irradiated the tissues of two different parts of the human body convert the said radiation fluxes reflected from the tissues into electrical signals carrying information about the parameters of the heart, provide synchronization of the said electrical signals, and on their basis, the biopotentials of the heart are determined.

The above technical results are also achieved by the fact that the above fluxes irradiate the tissues of the human body in the area of the right and left wrists.

The above technical results are also achieved by the fact that the mentioned sources with different wavelengths provide radiation of different polarizations.

The above technical results are also achieved by the fact that the received electrical signals, carrying information about the parameters of the heart, are sent to a remote server, where they are correlated and summed.

The above technical results are also achieved by the fact that the system for determining the parameters of the work of the heart contains the first and the second device for measuring the parameters of the work of the heart, the said devices are intended to be installed on various parts of the human body and each of them contains a housing, a power source installed inside the said housing at least two sources of laser radiation, each of which is equipped with a means of converting laser radiation into electrical signals carrying information about the parameters of the heart, a memory unit for recording information about the work of the heart, a unit for transmitting information about the parameters of the heart, while the system provides synchronization received electrical signals.

The above technical results are also achieved by the fact that each of the above devices contains at least two laser radiation sources made of diodes, one of them having a wavelength from 540nm to 550nm, and the second from 560nm to 570nm.

The above technical results are also achieved in that each of the above devices additionally contains a second pair of diode laser sources with wavelengths from 520nm to 528nm and from 532nm to 540nm, respectively.

The above technical results are also achieved by the fact that one of the laser radiation sources forming a pair provides longitudinal polarization, and the second - transverse.

The above technical results are also achieved by the fact that the said information transmission unit is made in the form of a wireless personal area network (WPAN) module.

The above technical results are also achieved in that each device contains a pulse generation module that provides pulsed laser radiation with a maximum frequency of 300 pulses per second, while the said pulse generation module is made adaptive with the ability to change the pulse frequency from 20 to 300 pulses per second.

The above technical results are also achieved in that the said memory unit is equipped with a means for compressing measurement information, each of the said devices contains a fastening means that allows the device to be mounted on a person's wrist in the form of a bracelet, while the system is equipped with a means for measuring blood pressure and means for measuring body temperature ...

The above technical results are also achieved in that the electronic device contains means for processing electrical signals carrying information about the parameters of the heart, to implement the method for determining the parameters of the heart in accordance with the present invention.

The above technical results are also achieved by the fact that the electronic device is made in the form of an integrated microcircuit.

The above technical results are also achieved by the fact that the said processing means are implemented in the form of software.

A distinctive feature of the present invention is the use of at least two devices equipped with at least two sources of laser radiation with different wavelengths, and each source is equipped with its own means of recording reflected radiation.

Short list of drawings

Figure 1 shows a general appearance of the device.

Figures 2 and 3 show the structure of the device with a different number of emitters.

Figure 4 shows a diagram of the interaction of the emitter and the recorder of the reflected signal.

Figure 5 shows the relationship of the reflected pulses with the elements of the cardiogram.

Figure 6 shows a diagram of the interaction of devices with a remote server

Implementation of the invention

Heart disease has come to the fore in recent decades as a cause of death and disability. In this regard, the task of developing new methods of diagnostics and monitoring of cardiac activity is becoming more and more urgent. Information about the parameters of cardiac activity is the basis for assessing the state of both individual organs and entire systems of human vital activity: the nervous system, adaptive capabilities, regulation systems, etc. There are numerous diagnostic methods of the psychophysiological state based on the analysis of heart rate variability. At the same time, any technique based on the analysis of heart rate requires effective means of obtaining accurate primary measurement information about the parameters of cardiac activity.

One of the most common methods of obtaining primary measurement information is an electrocardiogram (ECG). As you know, an electrocardiogram (ECG) is a periodically repeating curve of the biopotentials of the heart, reflecting the course of the process of excitation of the heart, which arose in the sinus (sinus-atrial) node and spreads throughout the heart, recorded using an electrocardiograph. Its individual elements - teeth, segments and intervals - have special names:

- teeth P, Q, R, S, T

- intervals PQ, QRS, QT, RR;

- segments PQ, ST, TP.

They characterize the emergence and spread of excitation through the atria (P), interventricular septum (Q), gradual excitation of the ventricles (R), maximum excitation of the ventricles (S), repolarization of the ventricles (S) of the heart. The P wave reflects the process of depolarization of both atria, the QRS complex reflects the depolarization of both ventricles, and its duration is the total duration of this process. The ST segment and the G wave correspond to the phase of ventricular repolarization. The duration of the PQ interval is determined by the time it takes for excitation to pass through the atria. The duration of the QR-ST interval is the duration of the "electrical systole" of the heart; it may not correspond to the duration of the mechanical systole.

An ECG is obtained using an electrocardiograph, an apparatus designed to display the work of the heart, by recording a curve. The electrocardiograph allows you to quickly record an ECG, registers and measures the potential difference of the heart from the surface of the human body, using the application of electrodes. It can work both in manual and automatic modes. As a rule, the functionality of the device depends on the field of application, however, absolutely all devices must meet the requirement of high quality of the recorded electrocardiogram. High-quality ECG in any conditions can be obtained with special filters.

The electrocardiograph has become widespread in medicine due to its relatively simple device and uncomplicated methods of operation. It is absolutely safe and does not create any discomfort or inconvenience for the patient.

The existing technologies for obtaining an ECG using an electrocardiograph are not very suitable for systems of long-term monitoring and observation of the patient's condition. ECG equipment is energy-consuming, massive, and it is difficult to ensure its reliable fixation on the patient's body while maintaining normal mobility. The existing portable equipment does not provide the sensitivity and accuracy of measurements sufficient to record the precursors of chronic changes and sudden complications in the activity of the heart.

The objective of the present invention is to provide a reliable and effective means for measuring and monitoring all parameters necessary for a complete analysis of cardiac activity (intensity of the P, Q, R, S, T waves). The information obtained with the help of this invention makes it possible to automate the calculation and analysis of the QRS complex, heart rate, Q-T, T-P, S-T intervals, etc.

The invention is based on the fact that the ability of red blood cells to reflect coherent radiation depends on the wavelength of the radiation and the phase of the heart. The intensity of the reflected waves is proportional to the number of red blood cells caught in the laser diode irradiation area. Thus, at each moment of time there is a correlation between the value of the biopotential of the heart and the intensity of the wave reflected from the patient's body.

The method for determining the parameters of the heart is that at least two independent streams of laser radiation are formed. Each of the streams includes radiation from at least two independent sources with different wavelengths. The mentioned fluxes irradiate tissues of two different parts of the human body. It is most advisable to irradiate tissues where the pulse is best felt, for example, on the wrists. It is also possible to direct the flow to body surfaces where there is minimal body fat, impairing the measurement accuracy, for example, on the shins.

Further, the said radiation fluxes reflected from the tissues are converted into electrical signals carrying information about the parameters of the heart, while synchronizing the said electrical signals is provided. On the basis of the recorded signals, the biopotentials of the heart are determined.

It is advisable that the above-mentioned sources with different wavelengths provide radiation of different polarization, for example, one source - parallel, the second - perpendicular.

The received electrical signals, carrying information about the parameters of the heart, can be sent to a remote server, where they are correlated and summed.

To carry out the method, the present invention includes an appropriate system.

The basis of the method and the corresponding system is the design of the device intended for installation on the human body.

As shown in Fig. 1, the device for measuring the parameters of the heart function comprises a housing 1 provided with a means 2 for attachment to the patient's body. The device can be equipped with a display 12 for displaying information about the parameters of the heart, as well as other information, such as time, date, etc.

Installation of devices is possible, in principle, on any part of the human body. It is most advisable to install the device on the patient's wrist in the zone of maximum pulse manifestation. However, the present method allows measurements to be taken anywhere on the patient's body, in particular in the area of the shoulders, chest, and lower extremities. The attachment means 2 can be made, for example, in the form of a strap, as shown in FIG. 1. In this case, the device is installed on the patient's wrist in the form of a bracelet.

A power source 3, one or more sources of laser radiation 4 and 5 is installed inside the housing 1. As shown in Fig. 2, in the case of several sources, each of them is equipped with means for converting laser radiation into an electrical signal carrying information about the parameters of the patient's heart ( items 6 and 7).

In the housing 1 there are also installed a memory unit 8 for recording information about the work of the heart and a unit 9 for transmitting information about the parameters of the work of the heart to external systems for processing and storing information, for example, to a cloud storage.

Preferably, the device may contain a pair of diode sources 4 and 5 of laser radiation with wavelengths from 540nm to 550nm and from 560nm to 570nm.

The device contains means for synchronizing the received electrical signals with the signals received by a similar device installed elsewhere on the body. synchronization can be performed in any known manner, for example by sending clock pulses to paired devices and waiting for a response from them. Based on the Marzullo algorithm, the signal delay time is calculated and an internal timer counter is set on the paired devices.

Molecular compounds of blood components (for example, hydroxyl groups in hemoglobin, etc.) have different values of natural frequencies and different ability to reflect optical radiation. In addition, blood components and tissue elements in the human body can occupy different spatial positions at different points in time. The essence of the invention consists in the simultaneous irradiation of the patient's body tissues with coherent radiation with two different wavelengths. In this case, radiation with one wavelength will receive the maximum response (in the form of a reflected wave) from one part of the molecular compounds and tissue elements, and radiation with a different wavelength will provide the maximum response from another part of the molecular compounds and elements. By adding the obtained values of the reflected signals, it is possible to obtain the most accurate correspondence with the actual value of the biopotential of the heart at each moment of time.

The device may additionally contain a second pair of diode sources 10 and 11 (Fig. 3) of laser radiation with wavelengths from 520nm to 528nm and from 532nm to 540nm. Accordingly, each additional source 10 and 11 of laser radiation is equipped with its own means of converting laser radiation into an electrical signal carrying information about the parameters of the patient's heart (positions 18 and 19).

An additional emitter-receiver pair increases the measurement accuracy of the reflected signal by providing even greater coverage of the response of molecular compounds, increasing the dynamic range and increasing the width of the spectral analysis.

It is advisable that one source of laser radiation in a pair provides longitudinal polarization, and the second - transverse. This is because the red blood cells in the body have different locations in space. The highest accuracy of the method is achieved when the polarization of the radiation coincides with the length of the blood cells. This makes it possible to exclude the influence of external illumination and obtain, after mathematical processing, a higher-quality general signal by adding two independent curves of the intensity of the reflected signal received from bodies with different spatial orientation.

Unit 9 for transmitting information about the parameters of the heart is made in the form of a wireless personal area network (WPAN) module, for example, the Bluetooth standard. As block 9, a wireless LAN module (for example, Wi-Fi) can be used.

The method used in the present invention makes it possible to obtain information with the required accuracy with constant radiation of sources 4, 5 and 10, 11. However, in a constant mode, the charge of the power supply is quickly consumed, despite the fact that for subsequent digitalization, the received reflected signal must be decrypted, quantized and etc. In the case of using a constant mode of operation of the emitters, the device can be equipped with an analog-to-digital converter (for example, with a capacity of 24 bits and an operating range from 1V to 3V). This will allow the measurement information to be digitized and processed using the processor 17.

It is most expedient to immediately provide a pulsed mode of operation of the emitters and converters 6, 7. For this purpose, the device preferably contains a pulse generating unit 13, which provides pulsed laser radiation with a maximum frequency of up to 300 pulses per second. Pulse mode increases the device's life due to reduced power consumption, provides filtering of shadow measurement, and reduces the time of exposure to the patient's body tissues.

The pulse generating unit 13 can be made adaptive with the ability to change the pulse frequency from 30 to 300 pulses per second with a duration b from 1 μs to 33 ms (Fig. 5). This improves the accuracy of exposure and the timely response of the device to deviations from the norm.

The memory unit 8 is equipped with means for compressing the measurement information. To do this, you can use the Wavelet Haar filter and the Huffman coding algorithm, which will allow you to record large data with low power consumption for processing on remote servers.

The device can additionally be provided with a blood pressure measuring means 14 and a patient temperature measuring means 16. As means 14, it is advisable to use low-power piezoelectric generators, which, as a result of vibrations from contact, generate a recording voltage from a pulse wave, and the recording of a pulse wave is also secondary.

The means for converting laser radiation into an electrical signal is expediently made in the form of a CCD element with an optical filter with an operating frequency range from 515 nm to 570 nm. Thus, unnecessary frequencies are removed, which may arise as a result of improper fit of the device or flare. This will, in turn, provide a more stable system response regardless of external noise and shadow current.

The device may contain means 15 for three-stage signal amplification with low, high and low pass filters connected in direct sequence. The optimal signal gain is from 10dBm to 18dBm.

The method consists in the fact that in different places on the human body (for example, in the area of the right and left wrists), two devices are installed that form at least two streams of laser radiation from at least two sources of laser radiation. The said streams of the human body tissue are irradiated at the locations of the devices, the reflected radiation is recorded and the said radiation streams reflected from the tissues are converted into electrical signals carrying information about the parameters of the heart. At the same time, synchronization of the received electrical signals is provided, and on their basis the biopotentials of the heart are determined in the form of a cardiogram.

The area of each wrist can be irradiated with at least two beams of laser radiation with different wavelengths in accordance with the functionality of the device described above.

The electrical signals received in the area of each wrist, carrying information about the parameters of the heart, are sent to a remote server, where they are logically added, as shown in Fig. 6.

Discrete signals from two or more sources are combined into one signal on the basis of accurate synchronization, thus a sampling frequency increased by two or more times, depending on the number of measuring instruments, is obtained, which gives more accurate results based on Fourier transforms.

Obviously, the device is based on electronic components containing means for processing electrical signals that carry information about the parameters of the heart. It is the electronic component that provides the implementation of the method in accordance with the invention.

An electronic device can be made in the form of an integrated microcircuit (hardware), in the form of software (software) or a combined software and hardware solution (firmware).

An electronic device for implementing the method can be built into any known medical device (for example, systems for physiotherapy), thereby expanding their functionality. An electronic device is built according to the well-known rules of circuitry using any components suitable for ensuring the functioning.

The invention is carried out as follows:

Two identical devices are created and installed in different places on the patient's body. For example, one device is placed on the wrist, the other on the foot.

As shown in Fig. 5, the pulse generating unit 13 generates rectangular pulses of a given duration b from 1 μs to 1 ms with a frequency of F up to 300 Hz and a power of up to 20 mW and directs them to the laser radiation sources 4 and 5. The current value of the frequency and duration of the pulses can be selected based on the patient's condition. For example, at night, when there is no physical activity in order to conserve energy, the frequency and duration of the impulses can be minimal. During periods of high physical activity or when cardiac information is needed with particularly high accuracy (for example, in pre-infarction conditions), the frequency increases. Thus, an adaptive mechanism for selecting radiation parameters is implemented depending on the conditions in which the patient is located and on the state of his health. The ability to adjust the radiation parameters allows you to choose the optimal operating mode of the device for people with various diseases.

The laser beam falls on the tissues 21 of the patient's body and, having reflected from them (including from red blood cells) 20, the beam is captured by means (position 6) of converting laser radiation (photodetector) into an electrical signal, as shown in Fig. 4. Thus, the reflected radiation is registered, which carries information about the parameters of the heart.

The signal from the photodetector is amplified by a three-stage amplifier with subsequent filtering of the signal.

In a constant mode of operation of the emitters, the device is equipped with a processor 17 and the signal is preliminarily fed to an analog-to-digital converter, and then the digitized signal is fed to the processing unit.

Reconstruction of the rectangular waveform is provided to obtain absorption coefficients and to select a more accurate time of arrival of the reflected signal.

When using adaptive algorithms, the frequency and duration of the subsequent measurement pulse can be determined based on various integral parameters, for example, depending on the intensity of the previous recorded pulse. This allows, for example, to increase the frequency and power of impulses at moments of unstable work of the heart to obtain more accurate bioinformation.

The signal is analyzed, compressed and sent to the memory unit 6 and through the unit 7 to the user's smartphone and then to the remote server for storing and processing information (Fig. 6).

The calculation of the cardiogram can be performed by decomposing the obtained discrete sequence of the reflected signal intensity into a Fourier series with frequency filtering to smooth the signal, followed by an inverse transformation to restore the desired heart rate curve.

As shown in Fig. 5, the reflected pulses carry information about the biopotential values of the heart. Registration and processing of reflected impulses allows you to determine with high accuracy all parameters inherent in the ECG and transfer this data for storage, processing and analysis to any computerized systems, both within one medical institution, and between different institutions united by a common network or having access to patient data warehouse.

The invention can be implemented by means of an electronic device that integrates into any diagnostic tools to expand their functionality.

Obtaining data on the biopotentials of the heart simultaneously from different parts of the patient's body allows obtaining more accurate data and reducing the likelihood of error.

Claims (12)

1. A method for determining the parameters of the heart, which consists in the fact that at least two streams of laser radiation are formed, each of which includes radiation from at least two sources with different wavelengths and different polarizations, these streams irradiate tissues of two different parts of the human body , convert said radiation streams reflected from tissues into electrical signals carrying information about the parameters of the heart, provide synchronization of said electrical signals, and on their basis determine the biopotentials of the heart. 2. A method according to claim 1, characterized in that said fluxes irradiate the tissues of the human body in the area of the right and left wrists. 3. The method according to claim 1, characterized in that the received electrical signals carrying information about the parameters of the heart are sent to a remote server, where they are correlated and summed. 4. A system for determining the parameters of the heart, containing the first and second devices for measuring the parameters of the heart, said devices are designed to be installed on different parts of the human body and each of them contains a housing installed inside the said housing, a power source, at least two laser sources radiation with different wavelengths and different polarizations, each of which is equipped with a means of converting laser radiation into electrical signals carrying information about the parameters of the heart, a memory unit for recording information about the work of the heart, a unit for transmitting information about the parameters of the heart, while the system provides synchronization received electrical signals. 5. The system according to claim 4, characterized in that each of said devices contains at least two sources of laser radiation made of diodes, one of them having a wavelength from 540 nm to 550 nm, and the second from 560 nm to 570 nm. 6. The system according to claim 5, characterized in that each of said devices further comprises a second pair of diode laser sources with wavelengths from 520 nm to 528 nm and from 532 nm to 540 nm, respectively. 7. The system according to claim 5 or 6, characterized in that one of the laser radiation sources forming a pair provides longitudinal polarization, and the second - transverse. 8. The system of claim. 4, characterized in that said information transmission unit is made in the form of a wireless personal area network (WPAN) module. 9. The system of claim give me a sec. 10. The system according to claim 4, characterized in that said memory unit is provided with means for compressing measurement information, each of said devices comprises fastening means that ensure the installation of the device on the wrist of a person in the form of a bracelet, wherein the system is equipped with a means for measuring blood pressure and means measuring body temperature. 11. An electronic device for determining the parameters of the heart, containing means for processing electrical signals carrying information about the parameters of the heart, to implement the method according to claim 1. 12. An electronic device according to claim 11, characterized in that it is made in the form of an integrated microcircuit.

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