Generation and analysis system for heart sound characteristic energy spectrum

Abstract

The invention relates to the technical field of heart information analysis, and discloses a heart sound characteristic energy spectrum generation and analysis system, which comprises an acquisition processing module for acquiring heart sound signals of a patient and performing frequency division processing on the acquired heart sound signals to remove impurity frequencies of different frequencies in heart sound signal acquisition; the preprocessing module is used for carrying out preprocessing and interval sequence extraction operation on the heart sound signals to obtain a heart sound time sequence; and the construction module is used for constructing amplitude points of the heart sound signals on the heart sound time sequence, and connecting adjacent amplitude points after the amplitude points are constructed, so as to form a heart sound characteristic energy spectrum. Compared with the prior art, the characteristic parameters of the extracted heart sound signals are compared with the preset characteristic parameter threshold values, the characteristic parameters of the heart sound signals which are not in the preset characteristic parameter threshold values are determined, finally comprehensive output of the characteristic parameters is completed, and doctors can be assisted in judging the positive and abnormal conditions of the heart sound in a visual and simple mode.

Description

Technical Field

[0001] The present invention relates to the technical field of cardiac information analysis, and in particular to a system for generating and analyzing a cardiac sound characteristic energy spectrum. Background Art

[0002] Heart sounds are produced by vibrations caused by myocardial contraction, heart valve closure, and blood hitting the ventricular walls and aorta walls. They are one of the most important physiological signals of the human body. When the human body has some diseases, heart sounds will produce some important pathological information, and these pathological information are characteristically manifested in many diseases. Therefore, by observing the changes in heart sound signals, a certain basis can be provided for the judgment of symptoms.

[0003] In the existing technology, the classification and recognition function of heart sounds mostly only distinguishes the signals of normal and abnormal heart sounds, and in the process of segmenting heart sounds, a single threshold is usually calculated for segmentation. This calculation method is easy to implement, but the accuracy of the calculation result is relatively inaccurate, and the anti-interference ability to external noise is not strong, which will cause serious errors in the segmentation of heart sounds, and further affect the patient's symptom judgment results. Summary of the invention

[0004] The purpose of the present invention is to provide a system for generating and analyzing a characteristic energy spectrum of heart sounds, determine the characteristic parameters of heart sound signals that are not within a preset characteristic parameter threshold, and finally complete the comprehensive output of the characteristic parameters, which can assist physicians in judging the positive and abnormal conditions of heart sounds in an intuitive and concise manner, aiming to solve the problems in the prior art.

[0005] The present invention is implemented as follows: a system for generating and analyzing a characteristic energy spectrum of heart sounds, comprising:

[0006] The acquisition and processing module is used to acquire the patient's heart sound signal and perform frequency division processing on the acquired heart sound signal to remove the impurity frequencies of different frequencies in the heart sound signal acquisition;

[0007] A preprocessing module is used to perform preprocessing and interval sequence extraction operations on the heart sound signal to obtain the heart sound time series;

[0008] A construction module is used to construct the amplitude points of the heart sound signal on the heart sound time series, and after the amplitude points are constructed, adjacent amplitude points are connected to form a heart sound characteristic energy spectrum;

[0009] an analysis module, configured to identify and read the formed heart sound characteristic energy spectrum, extract characteristic parameters of the heart sound signal from the heart sound characteristic energy spectrum, compare the extracted characteristic parameters of the heart sound signal with a preset characteristic parameter threshold, and determine the characteristic parameters of the heart sound signal that are not within the preset characteristic parameter threshold;

[0010] The output module is used to mark the characteristic parameters of the acquired heart sound signal that are not within the preset characteristic parameter threshold, and output and display the marking information after the marking is completed.

[0011] Furthermore, the acquisition and processing module includes:

[0012] The MCU module is used to send relevant instructions to control other modules in the system to complete the execution of relevant instructions, and also realize the reception of data collected by other modules in the system after completing relevant instructions;

[0013] Analog PID circuit is used to achieve precise control of proportional, integral and differential links by adjusting the parameters of resistance and capacitance components in the circuit;

[0014] An acquisition module, used for acquiring the patient's heart sound signals;

[0015] The denoising module is used to perform denoising on the heart sound signal collected by the collection module to remove impurity frequencies of different frequencies in the heart sound signal collection.

[0016] Furthermore, the heart sound signals acquired by the acquisition and processing module include a first heart sound, a second heart sound, a third heart sound, and a fourth heart sound. The first heart sound and the second heart sound can be captured under normal circumstances, the third heart sound can only be captured in children and adolescents, and the fourth heart sound cannot be captured under normal circumstances.

[0017] Furthermore, the acquisition module includes:

[0018] The first unit is used to capture and obtain a first heart sound in a heart sound signal of a patient;

[0019] The second unit is used to capture and obtain the second heart sound in the heart sound signal of the patient;

[0020] The third unit is used to capture and obtain the third heart sound in the patient's heart sound signal;

[0021] The fourth unit is used to capture and obtain the fourth heart sound in the patient's heart sound signal;

[0022] The interception unit intercepts and divides the first part of the signal waves of the identified first heart sound, second heart sound, third heart sound and fourth heart sound respectively, so that the first heart sound, second heart sound, third heart sound and fourth heart sound are separated to form the first heart sound signal wave, the second heart sound signal wave, the third heart sound signal wave and the fourth heart sound signal wave.

[0023] Furthermore, the denoising module performs denoising on the heart sound signal collected by the collection module to remove impurity frequencies of different frequencies in the heart sound signal collection, including the following steps:

[0024] Perform wavelet decomposition on the noisy heart sound signal, select the wavelet to determine the number of decomposition layers, and then perform multi-layer decomposition on the heart sound signal;

[0025] Determine the threshold of the high-frequency coefficients of wavelet decomposition, and select soft threshold or hard threshold quantization processing for the high-frequency coefficients from the first layer to the last layer;

[0026] The one-dimensional wavelet reconstruction after the quantization process is performed according to the low-frequency coefficients of the last layer of the wavelet decomposition and the high-frequency coefficients from the first layer to the last layer to obtain the reconstructed heart sound signal;

[0027] If the denoising effect after the heart sound signal reconstruction is not obvious, the above steps can be repeated for denoising until the impurity frequencies of different frequencies are completely removed and then stop.

[0028] Furthermore, the preprocessing module includes:

[0029] A filtering module is used to perform bandpass filtering and power frequency notch processing on the acquired first heart sound, second heart sound, third heart sound, and fourth heart sound respectively to remove baseline drift and power frequency interference, and then perform normalization processing;

[0030] The heart sound recognition module is used to set the interval sequence of the first heart sound, the second heart sound, the third heart sound and the fourth heart sound obtained, and after the setting is completed, the heart sound signals are synchronously captured respectively.

[0031] Furthermore, the preprocessing module also includes:

[0032] The wave point confirmation module acquires all the interval sequences in the heart sound signal by synchronously capturing the interval sequences, so as to complete the interval sequence extraction operation;

[0033] The generation module extracts all the interval sequences completed and aggregates them to form a heart sound time series.

[0034] Furthermore, the steps for performing preprocessing and interval sequence extraction operations on the heart sound signal to obtain the heart sound time series include:

[0035] Locate the starting point of the Q wave, the peak point of the R wave, the peak point and the end point of the T wave in the heart sound signal respectively;

[0036] The RR interval, QT interval, T wave peak-T wave end interval and Tpe / QT interval sequences were extracted, and the QT interval was corrected to obtain the corrected QT interval.

[0037] Furthermore, the building blocks include:

[0038] a conversion unit, configured to calculate the current frequencies of the first heart sound signal wave, the second heart sound signal wave, the third heart sound signal wave, and the fourth heart sound signal wave respectively for the acquired first heart sound signal wave, the second heart sound signal wave, the third heart sound signal wave, and the fourth heart sound signal wave, and to calculate the current amplitude values ​​of the first heart sound signal wave, the second heart sound signal wave, the third heart sound signal wave, and the fourth heart sound signal wave respectively according to the current frequencies;

[0039] The compensation unit is used to obtain the amplitude value of the heart sound signal in the current heart sound time series on the amplitude axis of the heart sound characteristic energy spectrum, connect adjacent amplitude points after construction is completed, form a heart sound characteristic energy spectrum, and then perform amplitude compensation on the formed heart sound characteristic energy spectrum.

[0040] Furthermore, the analysis module is used to identify and read the formed heart sound characteristic energy spectrum, and extract characteristic parameters of the heart sound signal from the heart sound characteristic energy spectrum, and the extracted characteristic parameters of the heart sound signal include:

[0041] The frequency, systolic and diastolic duration of the first, second, third and fourth heart sounds.

[0042] Compared with the prior art, the system for generating and analyzing the characteristic energy spectrum of heart sounds provided by the present invention has the following beneficial effects:

[0043] 1. By performing frequency division, preprocessing and interval sequence extraction operations on the patient's heart sound signal, the two are jointly analyzed to overcome the limitations of single signal analysis. A new method of forming a heart sound characteristic energy spectrum is used to construct the amplitude points of the heart sound signal on the heart sound time series, and the characteristic parameters of the heart sound signal are extracted from the heart sound characteristic energy spectrum. The characteristic parameters of the extracted heart sound signal are compared with the preset characteristic parameter threshold, and the characteristic parameters of the heart sound signal that are not within the preset characteristic parameter threshold are determined. Finally, the comprehensive output of the characteristic parameters is completed, which can assist doctors in judging the positive and abnormal conditions of heart sounds in an intuitive and concise way;

[0044] 2. The steps of obtaining the heart sound time series include: locating the starting point of the Q wave, the peak point of the R wave, the peak point and the end point of the T wave in the heart sound signal respectively; extracting the RR interval, QT interval, T wave peak-T wave end point interval and Tpe / QT interval sequence, and correcting the QT interval to obtain the corrected QT interval, using the phonocardiogram to locate the QT wave group in time, identifying heart abnormalities, and ensuring the accuracy of recognition. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 A schematic diagram of the structure of a system for generating and analyzing a characteristic energy spectrum of heart sounds proposed by the present invention;

[0046] Figure 2 This is a structural schematic diagram of a collection and processing module in a system for generating and analyzing a characteristic energy spectrum of heart sounds proposed by the present invention;

[0047] Figure 3 This is a schematic diagram of the structure of a preprocessing module in a system for generating and analyzing a heart sound characteristic energy spectrum proposed by the present invention;

[0048] Figure 4 It is a structural schematic diagram of a building block in a system for generating and analyzing a characteristic energy spectrum of heart sounds proposed by the present invention;

[0049] Figure 5 A heart sound characteristic energy spectrum generated by a heart sound characteristic energy spectrum generation and analysis system proposed by the present invention;

[0050] Figure 6 It is a schematic diagram of generating a first heart sound splitting spectrum in a heart sound characteristic energy spectrum generation and analysis system proposed by the present invention. DETAILED DESCRIPTION

[0051] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0052] The implementation of the present invention is described in detail below in conjunction with specific embodiments.

[0053] The same or similar numbers in the drawings of this embodiment correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the drawings, it is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes and cannot be understood as limitations on the present invention. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0054] Reference Figure 1-4 As shown, a system for generating and analyzing a heart sound characteristic energy spectrum includes:

[0055] The acquisition and processing module is used to acquire the patient's heart sound signal and perform frequency division processing on the acquired heart sound signal to remove the impurity frequencies of different frequencies in the heart sound signal acquisition. The heart sound signal acquired by the acquisition and processing module includes the first heart sound, the second heart sound, the third heart sound and the fourth heart sound. The first heart sound and the second heart sound can be captured under normal circumstances, the third heart sound can only be captured in children and adolescents, and the fourth heart sound cannot be captured under normal circumstances;

[0056] Among them, the acquisition and processing module includes:

[0057] The MCU module is used to send relevant instructions to control other modules in the system to complete the execution of relevant instructions, and also realize the reception of data collected by other modules in the system after completing relevant instructions;

[0058] Analog PID circuit is used to achieve precise control of proportional, integral and differential links by adjusting the parameters of resistance and capacitance components in the circuit;

[0059] An acquisition module, used for acquiring the patient's heart sound signals;

[0060] The denoising module is used to perform denoising on the heart sound signal collected by the collection module to remove impurity frequencies of different frequencies in the heart sound signal collection.

[0061] The acquisition module includes:

[0062] The first unit is used to capture and obtain a first heart sound in a heart sound signal of a patient;

[0063] The second unit is used to capture and obtain the second heart sound in the heart sound signal of the patient;

[0064] The third unit is used to capture and obtain the third heart sound in the patient's heart sound signal;

[0065] The fourth unit is used to capture and obtain the fourth heart sound in the patient's heart sound signal;

[0066] The interception unit intercepts and divides the first part of the signal waves of the identified first heart sound, second heart sound, third heart sound and fourth heart sound respectively, so that the first heart sound, second heart sound, third heart sound and fourth heart sound are separated into the first heart sound signal wave, the second heart sound signal wave, the third heart sound signal wave and the fourth heart sound signal wave;

[0067] A preprocessing module is used to perform preprocessing and interval sequence extraction operations on the heart sound signal to obtain the heart sound time series;

[0068] Among them, the preprocessing module includes:

[0069] A filtering module is used to perform bandpass filtering and power frequency notch processing on the acquired first heart sound, second heart sound, third heart sound, and fourth heart sound respectively to remove baseline drift and power frequency interference, and then perform normalization processing;

[0070] The heart sound recognition module is used to set the interval sequence of the first heart sound, the second heart sound, the third heart sound and the fourth heart sound, and after the setting is completed, the heart sound signals are synchronously captured respectively;

[0071] The wave point confirmation module acquires all the interval sequences in the heart sound signal by synchronously capturing the interval sequences, so as to complete the interval sequence extraction operation;

[0072] The generation module extracts all the completed interval sequences and aggregates them to form a heart sound time series;

[0073] A construction module is used to construct the amplitude points of the heart sound signal on the heart sound time series, and after the amplitude points are constructed, adjacent amplitude points are connected to form a heart sound characteristic energy spectrum;

[0074] The building blocks include:

[0075] a conversion unit, configured to calculate the current frequencies of the first heart sound signal wave, the second heart sound signal wave, the third heart sound signal wave, and the fourth heart sound signal wave respectively for the acquired first heart sound signal wave, the second heart sound signal wave, the third heart sound signal wave, and the fourth heart sound signal wave, and to calculate the current amplitude values ​​of the first heart sound signal wave, the second heart sound signal wave, the third heart sound signal wave, and the fourth heart sound signal wave respectively according to the current frequencies;

[0076] A compensation unit is used to obtain the amplitude value of the heart sound signal in the current heart sound time series on the amplitude axis of the heart sound characteristic energy spectrum, connect adjacent amplitude points after the construction is completed, form the heart sound characteristic energy spectrum, and then perform amplitude compensation of the heart sound signal on the formed heart sound characteristic energy spectrum;

[0077] An analysis module is used to identify and read the formed heart sound characteristic energy spectrum, extract characteristic parameters of the heart sound signal from the heart sound characteristic energy spectrum, and compare the extracted characteristic parameters of the heart sound signal with a preset characteristic parameter threshold to determine the characteristic parameters of the heart sound signal that are not within the preset characteristic parameter threshold;

[0078] The output module is used to mark the characteristic parameters of the acquired heart sound signals that are not within the preset characteristic parameter threshold. After the marking is completed, the marking information is output and displayed. By performing frequency division, line preprocessing and interval sequence extraction operations on the patient's heart sound signals, the two are jointly analyzed to overcome the limitations of single signal analysis. The amplitude points of the heart sound signals are constructed on the heart sound time series to form a new method of heart sound characteristic energy spectrum, and the characteristic parameters of the heart sound signals are extracted from the heart sound characteristic energy spectrum. The characteristic parameters of the extracted heart sound signals are compared with the preset characteristic parameter threshold to determine the characteristic parameters of the heart sound signals that are not within the preset characteristic parameter threshold. Finally, the comprehensive output of the characteristic parameters is completed, which can assist doctors in judging the positive and abnormal conditions of heart sounds in an intuitive and concise manner.

[0079] In this embodiment, the denoising module performs denoising on the heart sound signal collected by the collection module to remove impurity frequencies of different frequencies in the heart sound signal collection, including the following steps:

[0080] Perform wavelet decomposition on the noisy heart sound signal, select the wavelet to determine the number of decomposition layers, and then perform multi-layer decomposition on the heart sound signal;

[0081] Determine the threshold of the high-frequency coefficients of wavelet decomposition, and select soft threshold or hard threshold quantization processing for the high-frequency coefficients from the first layer to the last layer;

[0082] The one-dimensional wavelet reconstruction after the quantization process is performed according to the low-frequency coefficients of the last layer of the wavelet decomposition and the high-frequency coefficients from the first layer to the last layer to obtain the reconstructed heart sound signal;

[0083] If the denoising effect after the heart sound signal reconstruction is not obvious, the above steps can be repeated for denoising until the impurity frequencies of different frequencies are completely removed and then stop.

[0084] In this embodiment, the steps for performing preprocessing and interval sequence extraction operations on the heart sound signal to obtain the heart sound time series include:

[0085] Locate the starting point of the Q wave, the peak point of the R wave, the peak point and the end point of the T wave in the heart sound signal respectively;

[0086] The RR interval, QT interval, T wave peak-T wave end interval and Tpe / QT interval sequences were extracted, and the QT interval was corrected to obtain the corrected QT interval.

[0087] In this embodiment, the analysis module is used to identify and read the formed characteristic energy spectrum of heart sounds, and extract characteristic parameters of heart sound signals from the characteristic energy spectrum of heart sounds. The extracted characteristic parameters of heart sound signals include: the frequency, duration of systole and diastole of the first heart sound, the second heart sound, the third heart sound and the fourth heart sound.

[0088] The present invention performs frequency division, preprocessing and interval sequence extraction operations on the patient's heart sound signal, and jointly analyzes the two to overcome the limitations of single signal analysis. The present invention uses a new method of constructing the amplitude points of the heart sound signal on the heart sound time series to form a heart sound characteristic energy spectrum, and extracts characteristic parameters of the heart sound signal from the heart sound characteristic energy spectrum. The characteristic parameters of the extracted heart sound signal are compared with a preset characteristic parameter threshold to determine the characteristic parameters of the heart sound signal that are not within the preset characteristic parameter threshold. Finally, the comprehensive output of the characteristic parameters is completed, and the physician can be assisted in judging the positive and abnormal conditions of the heart sound in an intuitive and concise manner. At the same time, the steps of obtaining the heart sound time series include: locating the starting point of the Q wave, the peak point of the R wave, the peak point and the end point of the T wave in the heart sound signal respectively; extracting the RR interval, the QT interval, the T wave peak-T wave end point interval and the Tpe / QT interval sequence, and correcting the QT interval to obtain the corrected QT interval, using the phonocardiogram to locate the QT wave group of the time, identifying the abnormal heart condition, and ensuring the accuracy of the identification.

[0089] Reference Figure 5-6 The sound characteristic energy spectrum and the first heart sound splitting spectrum generated by the generation and analysis system of the heart sound characteristic energy spectrum of the present invention can determine the characteristic parameters of the heart sound signal that are not in the preset characteristic parameter threshold through spectrum observation and recognition, and finally complete the comprehensive output of the characteristic parameters, which can assist doctors in judging the positive and abnormal conditions of heart sounds in an intuitive and concise manner. The heart sound characteristic energy spectrum is generated by the Cohen-class time-frequency distribution method. By analyzing the samples of normal people and patients with mitral stenosis, obvious differences can be observed in the time-frequency energy spectrum, thereby effectively distinguishing normal and abnormal heart sounds and revealing the change process of heart sound frequency components over time. This method is helpful for the auxiliary diagnosis of heart disease and improves the accuracy and efficiency of diagnosis;

[0090] In this embodiment, the sounds produced when the heart contracts and relaxes can be divided into the first heart sound (S1) and the second heart sound (S2), both of which can be heard under normal circumstances. The third heart sound (S3 is usually only heard in children and adolescents), and the fourth heart sound (S4) are rarely heard under normal circumstances. The heart sounds produced by the heart are transmitted to the surface of the chest wall through the mediation of tissues. The heart sounds are a reflection of the mechanical movement of the heart and the cardiovascular system, which contain physiological and pathological information of the various parts of the heart and the interaction between them. The recognition and classification of heart sound signals are of great significance to the diagnosis of cardiovascular diseases. The accuracy and reliability of heart sound signals determine the effect of diagnosis and treatment of heart disease patients.

[0091] In this embodiment, heart sounds are mechanical vibrations caused by myocardial contraction and relaxation, valve opening and closing, blood flow impacting the ventricular wall and aorta during the cardiac cycle, which are transmitted to the chest wall through the surrounding tissues. By placing the ear close to the chest wall or placing the stethoscope on a certain position of the chest wall, it is usually easy to hear the first and second heart sounds, and sometimes the third or fourth heart sounds can be heard in certain circumstances.

[0092] In this embodiment, the first heart sound: S1 occurs at the beginning of the cardiac systole, has a low tone, and lasts for a long time (about 0.15 seconds). The causes include the contraction of the ventricular muscle, the sudden closure of the atrioventricular valve, and the vibration caused by the subsequent ejection of blood into the aorta. The best auscultation site for the first heart sound is in the fifth intercostal space of the midclavicular line or on the right edge of the sternum. It takes 0.08-0.15 seconds relative to 0.02-0.04 seconds after the start of the QRS wave on the electrocardiogram;

[0093] In this embodiment, the second heart sound: S2 occurs at the beginning of the diastole of the heart, with a higher frequency and a shorter duration (about 0.08 seconds). It is caused by the closure of the semilunar valves, the collision of the valves with each other, the deceleration of the blood in the aorta, and the vibration caused by the rapid drop in the chamber pressure. The best auscultation site of the second heart sound is the aortic valve area on the right side of the second intercostal space and the pulmonary valve area on the left side. Relative to the end of the T wave.

[0094] In this embodiment, the third heart sound S3 occurs 0.1 to 0.2 seconds after the second heart sound. It has a low frequency and is related to the rapid inflow of blood into the ventricle, which causes the ventricle and valve to vibrate. It is usually only heard by children because it is easier to transmit to the body surface. It is equivalent to 0.12 to 0.20 seconds after the T wave and the second heart sound.

[0095] In this embodiment, the fourth heart sound S4 is caused by atrial contraction, also known as atrial sound, which is equivalent to 0.15 to 0.18 seconds after the P wave on the electrocardiogram and has a low amplitude. Therefore, a compensation module is provided for compensation.

[0096] In this embodiment, since the heart sound signal is a weak biological signal of the human body under a strong noise background, and since the heart sound signal is an unstable natural signal emitted by a complex life form, changes in heart sounds and the appearance of murmurs are often early symptoms of organic heart disease, and changes in the physical structure of the heart will directly affect and change the heart sound signal.

[0097] In this embodiment, the abnormal first heart sound refers to S1 enhancement, weakening or splitting. S1 splitting refers to the distance between M1 and T1 being greater than 0.04 sec, which can be seen in normal children, young people and thin people, and has no important significance. When S1 is abnormally split, the distance between M1 and T1 can be greater than 0.06 seconds, which is seen in delayed electrical excitation (such as right bundle branch block, etc.), delayed mechanical activity (such as atrial septal defect, severe mitral stenosis, etc.). S1 splitting is most clear in the mitral and tricuspid valve areas by auscultation, and is clearer in the sitting position and when exhaling.

[0098] In this embodiment, the second heart sound is abnormal. S2 enhancement is divided into P2 enhancement and A2 enhancement. P2 enhancement is seen in increased pulmonary blood flow (such as septal defect), increased pulmonary vascular resistance, and increased pulmonary venous pressure (such as mitral stenosis). P2 hyperactivity is generally heard in the pulmonary valve area. A2 enhancement is seen in increased systemic circulation resistance or increased blood flow, which is transmitted to the pulmonary valve and apical area, and is seen in hypertension, etc.; S2 weakening is divided into P2 weakening and A2 weakening. P2 weakening is seen in low pulmonary artery pressure, reduced pulmonary blood flow or pulmonary valve stenosis, etc. A2 weakening is seen in low systemic circulation resistance, reduced blood flow, low blood pressure, aortic valve stenosis or severe regurgitation.

[0099] In this embodiment, abnormal S2 splitting includes wide splitting, fixed splitting, reverse splitting, and narrowed splitting. Wide splitting means that the S2 splitting does not disappear during exhalation, which is seen in cases such as prolonged right ventricular ejection time or shortened left ventricular ejection time. Fixed S2 splitting means that the A2-P2 interval does not change significantly during respiration or changes <0.02sec, which is seen in atrial septal defects with larger shunts. Reverse S2 splitting means that A2 is after P2, the A2-P2 splitting is not obvious during inspiration, P2 appears early during exhalation, and the splitting is widened. It is seen in delayed aortic valve closure. S2 splitting narrowing is often caused by the early appearance of P2 in severe pulmonary hypertension.

[0100] Traditional spectrum analysis methods use fast Fourier transform to associate time and frequency domains. For biological and physiological signals including human heart sound signals, they show non-stationary time-varying characteristics due to the influence of the environment. Therefore, it is difficult to accurately reflect the dynamic changes of heart sound signals using classical spectrum analysis methods.

[0101] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A system for generating and analyzing a characteristic energy spectrum of heart sounds, characterized in that: include: The acquisition and processing module is used to acquire the patient's heart sound signal and perform frequency division processing on the acquired heart sound signal to remove the impurity frequencies of different frequencies in the heart sound signal acquisition; A preprocessing module is used to perform preprocessing and interval sequence extraction operations on the heart sound signal to obtain the heart sound time series; A construction module is used to construct the amplitude points of the heart sound signal on the heart sound time series, and after the amplitude points are constructed, adjacent amplitude points are connected to form a heart sound characteristic energy spectrum; an analysis module, configured to identify and read the formed heart sound characteristic energy spectrum, extract characteristic parameters of the heart sound signal from the heart sound characteristic energy spectrum, compare the extracted characteristic parameters of the heart sound signal with a preset characteristic parameter threshold, and determine the characteristic parameters of the heart sound signal that are not within the preset characteristic parameter threshold; The output module is used to mark the characteristic parameters of the acquired heart sound signal that are not within the preset characteristic parameter threshold, and output and display the marking information after the marking is completed.

2. A system for generating and analyzing a characteristic energy spectrum of heart sounds as claimed in claim 1, characterized in that: The acquisition processing module includes: The MCU module is used to send relevant instructions to control other modules in the system to complete the execution of relevant instructions, and also realize the reception of data collected by other modules in the system after completing relevant instructions; Analog PID circuit is used to achieve precise control of proportional, integral and differential links by adjusting the parameters of resistance and capacitance components in the circuit; An acquisition module, used for acquiring the patient's heart sound signals; The denoising module is used to perform denoising on the heart sound signal collected by the collection module to remove impurity frequencies of different frequencies in the heart sound signal collection.

3. A system for generating and analyzing a characteristic energy spectrum of heart sounds as claimed in claim 2, characterized in that: The heart sound signals acquired by the acquisition and processing module include a first heart sound, a second heart sound, a third heart sound, and a fourth heart sound. The first heart sound and the second heart sound can be captured under normal circumstances, the third heart sound can only be captured in children and adolescents, and the fourth heart sound cannot be captured under normal circumstances.

4. A system for generating and analyzing a characteristic energy spectrum of heart sounds as claimed in claim 3, characterized in that: The acquisition module comprises: The first unit is used to capture and obtain a first heart sound in a heart sound signal of a patient; The second unit is used to capture and obtain the second heart sound in the heart sound signal of the patient; The third unit is used to capture and obtain the third heart sound in the patient's heart sound signal; The fourth unit is used to capture and obtain the fourth heart sound in the patient's heart sound signal; The interception unit intercepts and divides the first part of the signal waves of the identified first heart sound, second heart sound, third heart sound and fourth heart sound respectively, so that the first heart sound, second heart sound, third heart sound and fourth heart sound are separated to form the first heart sound signal wave, the second heart sound signal wave, the third heart sound signal wave and the fourth heart sound signal wave.

5. A system for generating and analyzing a characteristic energy spectrum of heart sounds as claimed in claim 4, characterized in that: The denoising module performs denoising on the heart sound signal collected by the collection module to remove impurity frequencies of different frequencies in the heart sound signal collection, including the following steps: Perform wavelet decomposition on the noisy heart sound signal, select the wavelet to determine the number of decomposition layers, and then perform multi-layer decomposition on the heart sound signal; Determine the threshold of the high-frequency coefficients of wavelet decomposition, and select soft threshold or hard threshold quantization processing for the high-frequency coefficients from the first layer to the last layer; The one-dimensional wavelet reconstruction after the quantization process is performed according to the low-frequency coefficients of the last layer of the wavelet decomposition and the high-frequency coefficients from the first layer to the last layer to obtain the reconstructed heart sound signal; If the denoising effect after the heart sound signal reconstruction is not obvious, the above steps can be repeated for denoising until the impurity frequencies of different frequencies are completely removed and then stop.

6. A system for generating and analyzing a characteristic energy spectrum of heart sounds as claimed in claim 5, characterized in that: The preprocessing module comprises: A filtering module is used to perform bandpass filtering and power frequency notch processing on the acquired first heart sound, second heart sound, third heart sound, and fourth heart sound respectively to remove baseline drift and power frequency interference, and then perform normalization processing; The heart sound recognition module is used to set the interval sequence of the first heart sound, the second heart sound, the third heart sound and the fourth heart sound obtained, and after the setting is completed, the heart sound signals are synchronously captured respectively.

7. A system for generating and analyzing a characteristic energy spectrum of heart sounds according to claim 6, characterized in that: The preprocessing module also includes: The wave point confirmation module acquires all the interval sequences in the heart sound signal by synchronously capturing the interval sequences, so as to complete the interval sequence extraction operation; The generation module extracts all the interval sequences completed and aggregates them to form a heart sound time series.

8. A system for generating and analyzing a characteristic energy spectrum of heart sounds as claimed in claim 7, characterized in that: The steps for preprocessing the heart sound signal and extracting the interval sequence to obtain the heart sound time series include: Locate the starting point of the Q wave, the peak point of the R wave, the peak point and the end point of the T wave in the heart sound signal respectively; The RR interval, QT interval, T wave peak-T wave end interval and Tpe / QT interval sequences were extracted, and the QT interval was corrected to obtain the corrected QT interval.

9. A system for generating and analyzing a characteristic energy spectrum of heart sounds as claimed in claim 8, characterized in that: The building blocks include: a conversion unit, configured to calculate the current frequencies of the first heart sound signal wave, the second heart sound signal wave, the third heart sound signal wave, and the fourth heart sound signal wave respectively for the acquired first heart sound signal wave, the second heart sound signal wave, the third heart sound signal wave, and the fourth heart sound signal wave, and to calculate the current amplitude values ​​of the first heart sound signal wave, the second heart sound signal wave, the third heart sound signal wave, and the fourth heart sound signal wave respectively according to the current frequencies; The compensation unit is used to obtain the amplitude value of the heart sound signal in the current heart sound time series on the amplitude axis of the heart sound characteristic energy spectrum, connect adjacent amplitude points after construction is completed, form a heart sound characteristic energy spectrum, and then perform amplitude compensation on the formed heart sound characteristic energy spectrum.

10. A system for generating and analyzing a characteristic energy spectrum of heart sounds according to claim 9, characterized in that: The analysis module is used to identify and read the formed heart sound characteristic energy spectrum, and extract characteristic parameters of the heart sound signal from the heart sound characteristic energy spectrum. The extracted characteristic parameters of the heart sound signal include: The frequency, systolic and diastolic duration of the first, second, third and fourth heart sounds.

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