Real-time monitoring and intelligent early warning bracelet for myocardial ischemia of patient with coronary heart disease

Abstract

The invention relates to the technical field of medical informatics, in particular to a real-time monitoring and intelligent early warning bracelet for myocardial ischemia of a patient with coronary heart disease. The bracelet comprises a memory and a processor, and the processor executes a computer program stored in the memory so as to realize the following steps: acquiring an electrocardiogram signal and different index data of a to-be-tested person, according to the symmetry of the amplitudes of the sampling points in the neighborhood of the peak point closest to each sampling point and the consistency of the inclination changes of each sampling point and the peak point closest to the sampling point, the ST-T property of each sampling point is obtained, and the blood oxygen saturation standard degree of each sampling point is determined in combination with the blood oxygen saturation data; combining the heart rate abnormity degree and the blood oxygen saturation standard degree of each sampling point to obtain a myocardial ischemia index corresponding to each sampling point; and judging whether to carry out early warning or not according to the difference between the heart rate abnormality and the blood pressure abnormality of each sampling point and the myocardial ischemia index. According to the invention, the credibility of the early warning result is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of medical informatics, and in particular to a real-time monitoring and intelligent early warning wristband for myocardial ischemia in patients with coronary heart disease. Background Art

[0002] Myocardial ischemia in patients with coronary artery disease (CAD) refers to a condition in which myocardial blood flow is insufficient due to narrowing or blockage of the coronary arteries, resulting in ischemia in certain areas of the heart. As a chronic disease, CAD requires long-term heart health management. The early warning function of a smart bracelet can provide timely alerts to patients experiencing potential heart problems. When a CAD patient experiences symptoms such as myocardial ischemia, the bracelet not only notifies the patient and their family immediately but also establishes an emergency connection with a medical institution, buying precious time for treatment.

[0003] When using a smart early warning bracelet to monitor a single-lead electrocardiogram (ECG) signal to warn of myocardial ischemia in patients with coronary artery disease, the primary approach is to assess ST segment elevation or T wave changes in the ECG. ST segment elevation typically indicates myocardial ischemia or myocardial infarction. T wave changes, such as T wave inversion or flattening, can be early signs of myocardial ischemia.

[0004] According to existing diagnostic knowledge, the electrocardiogram manifestations of myocardial ischemia in patients with coronary heart disease may be ST segment changes or T wave changes. However, in addition to coronary heart disease, similar ST-T changes may also occur in cardiomyopathy, myocarditis, valvular disease, pericarditis, cerebrovascular accident, etc.; in addition, electrolyte disorders such as hypokalemia and hyperkalemia, certain drugs (such as digitalis, quinidine, etc.), and autonomic nervous system regulation disorders may also cause ST-T changes; ventricular hypertrophy, bundle branch block, preexcitation syndrome, etc. can also lead to secondary ST-T changes. These factors may cause traditional smart bracelets to misjudge ST-T changes in non-coronary heart disease patients as myocardial ischemia in patients with coronary heart disease when issuing warnings, thereby making the warning signal inaccurate and reducing the credibility of the warning results. Summary of the Invention

[0005] In order to solve the problem of low warning reliability in existing methods for myocardial ischemia in patients with coronary heart disease, the present invention aims to provide a real-time monitoring and intelligent warning wristband for myocardial ischemia in patients with coronary heart disease. The technical solutions adopted are as follows:

[0006] The present invention provides a real-time monitoring and intelligent early warning wristband for myocardial ischemia in patients with coronary heart disease, comprising a memory and a processor. The processor executes a computer program stored in the memory to implement the following steps:

[0007] Obtaining electrocardiogram signals and different indicator data of the person to be tested, wherein the indicator data includes blood oxygen saturation data, heart rate data and blood pressure data;

[0008] Obtaining the ST-T characteristic of each sampling point based on the symmetry of the amplitudes of the sampling points in the neighborhood of the peak point closest to each sampling point on the electrocardiogram signal and the consistency of the tilt changes of each sampling point and the peak point closest to it; and determining the blood oxygen saturation standard of each sampling point by combining the ST-T characteristic and the corresponding blood oxygen saturation data;

[0009] Based on the difference in ST-T characteristics between each sampling point and other sampling points and the difference in similar indicator data, the abnormality of each type of indicator at each sampling point is evaluated; combined with the heart rate abnormality and blood oxygen saturation standard of each sampling point, the myocardial ischemia index corresponding to each sampling point is obtained;

[0010] The difference between the heart rate abnormality and the blood pressure abnormality at each sampling point and the myocardial ischemia index are combined to obtain a myocardial ischemia evaluation value; based on the myocardial ischemia evaluation value, it is determined whether to issue an early warning through the smart early warning bracelet worn by the person to be tested.

[0011] Preferably, obtaining the ST-T property of each sampling point based on the symmetry of the amplitudes of the sampling points in the neighborhood of the peak point closest to each sampling point on the electrocardiogram signal and the consistency of the tilt changes of each sampling point and the peak point closest to it includes:

[0012] For any peak point on the electrocardiogram signal: obtaining a symmetry factor of the peak point according to the symmetry of the amplitudes of the sampling points on the left and right sides of the peak point in the neighborhood of the peak point;

[0013] For any sampling point on the electrocardiogram signal: the ST-T characteristic of the any sampling point is obtained based on the slope difference between the any sampling point and the peak point closest to the any sampling point, and the symmetry factor of the peak point closest to the any sampling point, wherein the slope difference is negatively correlated with the ST-T characteristic, and the symmetry factor is positively correlated with the ST-T characteristic.

[0014] Preferably, obtaining the symmetry factor of any peak point according to the symmetry of the amplitudes of the sampling points on the left and right sides of any peak point in the neighborhood of any peak point includes:

[0015] Calculate the amplitude difference between two sampling points with the same time interval as the peak point in the neighborhood of the peak point respectively;

[0016] The symmetry factor of any peak point is obtained according to the sum of all the amplitude differences in the neighborhood of any peak point, and the sum is negatively correlated with the symmetry factor.

[0017] Preferably, the combining of the ST-T property and the corresponding blood oxygen saturation data to determine the blood oxygen saturation standard of each sampling point includes:

[0018] For any sampling point, a first difference between the blood oxygen saturation data of the any sampling point and a preset value is calculated; and the product of the negative correlation normalization result of the first difference and the ST-T characteristic of the any sampling point is determined as the blood oxygen saturation standard of the any sampling point.

[0019] Preferably, the evaluation of the abnormality of each type of indicator at each sampling point based on the difference in ST-T between each sampling point and other sampling points and the difference in similar indicator data includes:

[0020] For any sampling point:

[0021] The abnormality degree of each type of indicator at any sampling point is obtained based on the numerical proportion of the negative correlation normalized value of the ST-T characteristic at each sampling point on the electrocardiogram signal in the overall distribution of the negative correlation normalized value of the ST-T characteristic at all sampling points, and the difference between each type of indicator data at any sampling point and all sampling points. The numerical proportion and the difference between each type of indicator data are both positively correlated with the abnormality degree.

[0022] Preferably, obtaining the numerical proportion of the negative correlation normalized value of the ST-T characteristic at each sampling point on the electrocardiogram signal in the overall distribution of the negative correlation normalized values ​​of the ST-T characteristic at all sampling points includes:

[0023] Calculate the cumulative sum of the negative correlation normalized values ​​of ST-T of all sampling points;

[0024] The ratio of the negative correlation normalized value of the ST-T property of each sampling point to the cumulative sum is used as the numerical ratio corresponding to each sampling point.

[0025] Preferably, the step of combining the heart rate abnormality and blood oxygen saturation standard of each sampling point to obtain the myocardial ischemia index corresponding to each sampling point includes:

[0026] For any sampling point:

[0027] A myocardial ischemia index corresponding to any sampling point is obtained according to the heart rate abnormality degree of any sampling point and the blood oxygen saturation standard degree of any sampling point, and both the heart rate abnormality degree and the blood oxygen saturation standard degree are positively correlated with the myocardial ischemia index.

[0028] Preferably, the step of integrating the difference between the heart rate abnormality and the blood pressure abnormality at each sampling point and the myocardial ischemia index to obtain a myocardial ischemia evaluation value includes:

[0029] For any sampling point:

[0030] calculating a second difference between the heart rate abnormality degree and the blood pressure abnormality degree at any of the sampling points;

[0031] A myocardial ischemia evaluation value of any sampling point is obtained based on the second difference and the myocardial ischemia index corresponding to any sampling point, wherein the second difference is negatively correlated with the myocardial ischemia evaluation value, and the myocardial ischemia index is positively correlated with the myocardial ischemia evaluation value.

[0032] Preferably, obtaining the myocardial ischemia evaluation value of any sampling point according to the second difference and the myocardial ischemia index corresponding to any sampling point includes:

[0033] The product of the negative correlation normalized value of the second difference and the myocardial ischemia index corresponding to any one of the sampling points is used as the myocardial ischemia evaluation value of any one of the sampling points.

[0034] Preferably, the step of determining whether to issue an early warning through a smart early warning bracelet worn by the person to be tested based on the myocardial ischemia evaluation value includes:

[0035] If the total number of sampling points with myocardial ischemia evaluation values ​​greater than the preset evaluation threshold is greater than the preset number, an early warning will be issued through the smart early warning bracelet worn by the person to be tested;

[0036] If the total number of sampling points whose myocardial ischemia evaluation values ​​are greater than the preset evaluation threshold is less than or equal to the preset number, no warning is issued.

[0037] The present invention has at least the following beneficial effects:

[0038] In view of the problem that the existing technology is difficult to distinguish ST-T changes caused by myocardial ischemia in patients with coronary heart disease from those caused by other reasons, thereby resulting in low credibility of early warning of myocardial ischemia in patients with coronary heart disease, the present invention takes into account the symmetry of the peak points of ST-T changes, and can judge whether the peak point shows ST-T characteristics based on this characteristic. If the peak point shows ST-T characteristics and the sampling point is symmetrical about the peak point, then the sampling point also has ST-T characteristics; therefore, the symmetry of the amplitude of the sampling points in the neighborhood of the peak point closest to each sampling point on the electrocardiogram signal, as well as the consistency of the tilt change of each sampling point and the peak point closest to it are evaluated. A comprehensive analysis was conducted to evaluate the ST-T characteristics of each sampling point. However, other factors may also cause ST-T characteristics, so it is necessary to further verify whether these sampling points meet the characteristics of myocardial ischemia in patients with coronary heart disease. To this end, the blood oxygen saturation data was first combined to determine the blood oxygen saturation standard of each sampling point. Further combined with abnormal heart rate and the abnormal relationship between blood pressure and heart rate, it was finally determined that each sampling point met the myocardial ischemia degree of patients with coronary heart disease under ST-T characteristics conditions, and the myocardial ischemia evaluation value was obtained. Then, it was determined whether an early warning should be issued through the smart early warning bracelet worn by the person to be tested, thereby improving the credibility of the early warning results. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions and advantages of the embodiments of the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the prior art descriptions. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0040] Figure 1 This is a flow chart of a method performed by a real-time monitoring and intelligent early warning bracelet for myocardial ischemia in patients with coronary heart disease provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0041] In order to further illustrate the technical means and effects adopted by the present invention to achieve the predetermined purpose of the invention, the following is a detailed description of a real-time monitoring and intelligent early warning bracelet for myocardial ischemia in patients with coronary heart disease proposed by the present invention in combination with the accompanying drawings and preferred embodiments.

[0042] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0043] The following describes in detail a specific scheme of a real-time monitoring and intelligent early warning wristband for myocardial ischemia in patients with coronary heart disease provided by the present invention in conjunction with the accompanying drawings.

[0044] An embodiment of a real-time monitoring and intelligent early warning wristband for myocardial ischemia in patients with coronary heart disease:

[0045] The specific scenario targeted by this embodiment is: in the process of real-time monitoring of myocardial ischemia in patients with coronary heart disease, real-time monitoring of patients with coronary heart disease is carried out with the help of a smart early warning bracelet, and different types of monitoring data are collected. The changing characteristics and correlation characteristics of these data are used to determine whether there is any abnormality in the person to be tested at the current moment. If an abnormality occurs, a timely early warning is issued to increase attention to the patient and deal with the problem in a timely manner.

[0046] This embodiment proposes a real-time monitoring and intelligent early warning wristband for myocardial ischemia in patients with coronary heart disease. Figure 1 As shown, a wristband for real-time monitoring and intelligent early warning of myocardial ischemia in patients with coronary heart disease in this embodiment includes a memory and a processor. The processor executes a computer program stored in the memory to implement the following steps:

[0047] Step S1, obtaining an electrocardiogram signal and different index data of a person to be tested, wherein the index data includes blood oxygen saturation data, heart rate data and blood pressure data.

[0048] First, the person to be tested is given a smart early warning bracelet. The bracelet can collect the person's physiological data in real time through the built-in sensor, including the original single-lead electrocardiogram (ECG) signal. At the same time, a watch is used to collect different indicator data of the person to be tested at each sampling moment. In this embodiment, the different indicator data include blood oxygen saturation data, heart rate data, and blood pressure data. The implementer sets the frequency of indicator data collection according to the specific situation.

[0049] So far, this embodiment has collected the electrocardiogram signal, blood oxygen saturation data, heart rate data and blood pressure data of the person to be tested.

[0050] Step S2: Obtain the ST-T characteristic of each sampling point based on the symmetry of the amplitudes of the sampling points in the neighborhood of the peak point closest to each sampling point on the electrocardiogram signal, and the consistency of the tilt changes of each sampling point and the peak point closest to it; and determine the blood oxygen saturation standard of each sampling point by combining the ST-T characteristic and the corresponding blood oxygen saturation data.

[0051] First, all peak points are calculated and identified on the electrocardiogram signal. The method for obtaining the peak points on the curve is an existing technology and will not be described in detail here.

[0052] When myocardial ischemia occurs in patients with coronary heart disease, local oxygen deficiency shortens the cell action potential duration (APD). At the same time, the difference in repolarization speed between the ischemic and non-ischemic areas increases, thereby forming a potential gradient that is symmetrical about the peak. In addition, ischemia inhibits potassium outflow and enhances calcium inflow, which leads to a change in the symmetry of the repolarization slope, manifested as symmetrical inversion of the T wave. Symmetrical elevation of the ST segment (such as acute myocardial infarction) reflects transmural ischemia, forming a symmetrical current vector between the damaged area and the normal area, making the ST segment appear symmetrical with the back arched upward. Therefore, for each sampling point, if the nearest peak point corresponding to it is to show ST-, the two sides are often symmetrical.

[0053] Based on the above characteristics, this embodiment then evaluates the symmetry of the left and right sides of each peak point on the electrocardiogram signal. This embodiment will take any peak point on the electrocardiogram signal as an example for explanation. For other peak points, the method provided in this embodiment can be used for processing.

[0054] For any peak point in the ECG signal, the symmetry factor of the peak point is determined based on the symmetry of the amplitudes of the sampling points on the left and right sides of the peak point within the peak point's neighborhood. Specifically, the amplitude difference between two sampling points within the peak point's neighborhood that are equally spaced apart is calculated. The symmetry factor of the peak point is obtained by summing all of these amplitude differences within the peak point's neighborhood. This sum is negatively correlated with the symmetry factor.

[0055] Among them, the negative correlation relationship means that the dependent variable will decrease as the independent variable increases, and the dependent variable will increase as the independent variable decreases. It can be a subtraction relationship, a division relationship, etc., which is determined by actual application.

[0056] In this embodiment, a specific calculation formula for the symmetry factor is given. The symmetry factor of the r-th peak point on the electrocardiogram signal can be expressed as:

[0057]

[0058] Among them, S r Represents the symmetry factor of the rth peak point on the ECG signal, f′ r,j represents the amplitude of the jth sampling point to the left of the rth peak point in the neighborhood of the rth peak point, f″ r,j represents the amplitude of the jth sampling point to the right of the rth peak point in the neighborhood of the rth peak point, m represents the number of sampling points to the left or right of the rth peak point in the neighborhood, exp() represents the exponential function with a natural constant as the base, and || represents the absolute value sign.

[0059] It should be noted that in this embodiment, the neighborhood is a time neighborhood. The sampling point to the left of the r-th peak point and adjacent to the r-th peak point is the first sampling point to the left of the r-th peak point in the neighborhood of the r-th peak point, that is, from right to left, the first sampling point to the left of the r-th peak point in the neighborhood of the r-th peak point, the second sampling point to the left of the r-th peak point in the neighborhood of the r-th peak point, the third sampling point to the left of the r-th peak point in the neighborhood of the r-th peak point, and so on. The sampling point to the right of the r-th peak point and adjacent to the r-th peak point is the first sampling point to the right of the r-th peak point in the neighborhood of the r-th peak point, that is, from left to right, the first sampling point to the right of the r-th peak point in the neighborhood of the r-th peak point, the second sampling point to the right of the r-th peak point in the neighborhood of the r-th peak point, the third sampling point to the right of the r-th peak point in the neighborhood of the r-th peak point, and so on. In this embodiment, the value of m is set to 10. In specific applications, the implementer can set it according to specific circumstances.

[0060] |f′ r,j -f″ r,j Represents the amplitude difference between the jth sampling point on the left and right sides of the rth peak point within the neighborhood of the rth peak point. A smaller amplitude difference between two sampling points with equal time intervals within the neighborhood of the rth peak point indicates a higher symmetry of the ECG signal on the left and right sides of the rth peak point, that is, a larger symmetry factor for the rth peak point in the ECG signal.

[0061] In the above process, the symmetry of the sampling points within the temporal neighborhood of the normal ST-T peak is used to determine the symmetry factor of the peak point, which can be used to characterize the ST-T characteristics of the peak point. However, this does not mean that the neighborhood beyond the peak point lacks ST-T characteristics. In the electrocardiogram (ECG) signals of patients with myocardial ischemia due to coronary artery disease, the symmetry of the ST-T segment slope changes is primarily due to changes in the electrophysiological consistency of the myocardial repolarization process. ST segment changes are generally correlated with the degree of myocardial ischemia. ST segment elevation or depression exhibits regularity within a certain range, and T wave reversal is also related to the degree of ischemia. These changes typically exhibit certain temporal characteristics. Specifically, when ischemia occurs, the rate of change (i.e., slope) of the ST-T segment is often relatively constant. Because the electrophysiological characteristics of the ischemic myocardium stabilize in the early stages, the rate of change of the ST-T segment slope in the ECG generally remains stable.

[0062] From the above characteristics, it can be seen that if the ST-T characteristic at the peak point is high and the tilt change of the sampling point is consistent with the tilt change of the peak point, it can be considered that the ST-T characteristic is also present in the ST-T segment closest to the peak point.

[0063] For any sampling point on the electrocardiogram signal: the ST-T characteristic of the sampling point is obtained based on the slope difference between the sampling point and the peak point closest to it, and the symmetry factor of the peak point closest to the sampling point. The slope difference is negatively correlated with the ST-T characteristic, and the symmetry factor is positively correlated with the ST-T characteristic.

[0064] Among them, a positive correlation relationship indicates that the dependent variable will increase as the independent variable increases, and the dependent variable will decrease as the independent variable decreases. It can be an additive relationship, a multiplicative relationship, etc., which is determined by actual application; a negative correlation relationship indicates that the dependent variable will decrease as the independent variable increases, and the dependent variable will increase as the independent variable decreases. It can be a subtractive relationship, a division relationship, etc., which is determined by actual application.

[0065] In this embodiment, a specific calculation formula for the ST-T characteristic is given. The ST-T characteristic of the i-th sampling point on the electrocardiogram signal can be expressed as:

[0066] T i =exp(-|k i -k i ′ |)×S i ′

[0067] Among them, T i represents the ST-T property of the i-th sampling point on the ECG signal, k i represents the slope of the i-th sampling point on the ECG signal, k i ′ S represents the slope of the peak point on the ECG signal that is closest to the i-th sampling point. i ′ Indicates the symmetry factor of the peak point closest to the i-th sampling point on the ECG signal.

[0068] |k i -k i ′ Represents the slope difference between the i-th sampling point and the nearest peak point on the ECG signal. A larger absolute value indicates less consistent tilt changes at the two locations. The smaller the slope difference between the i-th sampling point and the nearest peak point, and the larger the symmetry factor of the nearest peak point, the greater the ST-T consistency of the i-th sampling point.

[0069] By using the above method, the ST-T characteristics of each sampling point on the electrocardiogram signal can be obtained.

[0070] In addition to coronary heart disease, similar ST-T changes may also occur in cardiomyopathy, myocarditis, valvular disease, pericarditis, cerebrovascular accident (especially intracranial hemorrhage), etc.; in addition, electrolyte disorders such as hypokalemia and hyperkalemia, certain drugs (such as digitalis, quinidine, etc.), and autonomic nervous system regulation disorders may also cause ST-T changes; ventricular hypertrophy, bundle branch block, preexcitation syndrome, etc. can also lead to secondary ST-T changes. Therefore, in order to ensure the accuracy of the smart early warning bracelet, this embodiment needs to combine other factors to evaluate each sampling point under ST-T characteristics to determine whether it is consistent with myocardial ischemia in patients with coronary heart disease.

[0071] After obtaining the ST-T characteristics of each sampling point on the electrocardiogram signal, the blood oxygen saturation is first analyzed. Under normal circumstances, the blood oxygen saturation should be maintained between 95% and 100%. If the blood oxygen saturation is lower than the normal range, it may indicate the presence of myocardial ischemia consistent with coronary heart disease patients.

[0072] Next, this embodiment is described by taking a sampling point on an electrocardiogram signal as an example. Other sampling points on the electrocardiogram signal can be processed using the method provided in this embodiment.

[0073] For any sampling point, the absolute value of the difference between the blood oxygen saturation data of the sampling point and the preset value is calculated. The absolute value is used to reflect the difference between the blood oxygen saturation data of the sampling point and the preset value, and the absolute value is recorded as the first difference; the product of the negative correlation normalization result of the first difference and the ST-T characteristic of the sampling point is determined as the blood oxygen saturation standard of the sampling point.

[0074] In this embodiment, a specific calculation formula for the blood oxygen saturation standard is given. The blood oxygen saturation standard of the i-th sampling point on the electrocardiogram signal can be expressed as:

[0075] G i =exp(-|Y i -Y0|)×T i

[0076] Among them, G i Indicates the blood oxygen saturation standard of the i-th sampling point on the electrocardiogram signal, Y i represents the blood oxygen saturation data of the i-th sampling point, Y0 represents the preset value, T i Indicates the ST-T characteristic of the i-th sampling point on the ECG signal.

[0077] |Y i -Y0| represents the first difference corresponding to the i-th sampling point, exp(-|Y i-Y0|) represents the negative correlation normalization result of the first difference. The smaller the difference between the blood oxygen saturation data at the i-th sampling point and the preset value, and the greater the ST-T coefficient of the i-th sampling point, the greater the standardization of the blood oxygen saturation at the i-th sampling point. In this embodiment, the preset value is 95. In specific applications, the implementer can set it according to specific circumstances.

[0078] By using the above method, the blood oxygen saturation standard of each sampling point on the electrocardiogram signal can be obtained.

[0079] Step S3: Evaluate the abnormality of each type of indicator at each sampling point based on the difference in ST-T characteristics between each sampling point and other sampling points and the difference in similar indicator data; combine the heart rate abnormality and blood oxygen saturation standard of each sampling point to obtain the myocardial ischemia indicator corresponding to each sampling point.

[0080] Based on the above-described determination of the blood oxygen saturation standard for myocardial ischemia in patients with coronary artery disease under ST-T characteristics at each sampling point, the heart rate is further used to preliminarily determine whether each sampling point meets the criteria for myocardial ischemia in patients with coronary artery disease under ST-T characteristics. Because both a fast or slow heart rate can be a manifestation of myocardial ischemia, a significant difference in heart rate at a sampling point compared to other points with smaller ST-T characteristics may indicate myocardial ischemia.

[0081] Next, this embodiment will first analyze the differences in ST-T characteristics between each sampling point and other sampling points and the differences in similar indicator data, evaluate the abnormality of each type of indicator at each sampling point, and then evaluate the myocardial ischemia condition in combination with the heart rate abnormality and blood oxygen saturation standard.

[0082] Specifically, this embodiment is still described by taking a sampling point on the electrocardiogram signal as an example, and other sampling points on the electrocardiogram signal can be processed using the method provided in this embodiment.

[0083] For any sampling point on the ECG signal:

[0084] The abnormality of each type of indicator at any sampling point is obtained based on the numerical proportion of the negative correlation normalized value of the ST-T characteristic at each sampling point on the electrocardiogram signal in the overall distribution of the negative correlation normalized value of the ST-T characteristic at all sampling points, and the difference between the data of each type of indicator at the sampling point and all sampling points. The numerical proportion and the difference of the data of each type of indicator are both positively correlated with the abnormality.

[0085] Among them, the specific process of obtaining the numerical proportion of the negative correlation normalized value of the ST-T property at each sampling point on the electrocardiogram signal in the overall distribution of the negative correlation normalized values ​​of the ST-T property at all sampling points is: calculating the cumulative sum of the negative correlation normalized values ​​of the ST-T property at all sampling points; and taking the ratio of the negative correlation normalized value of the ST-T property at each sampling point on the electrocardiogram signal to the cumulative sum as the numerical proportion of the negative correlation normalized value of the ST-T property at each sampling point in the overall distribution of the negative correlation normalized values ​​of the ST-T property at all sampling points.

[0086] In this embodiment, a specific calculation formula for the abnormality degree is given. The abnormality degree of the b-th category indicator at the i-th sampling point can be expressed as:

[0087]

[0088] Among them, C i,b represents the abnormality of the b-th indicator at the i-th sampling point, J represents the number of sampling points on the ECG signal, T j Indicates the ST-T property of the jth sampling point on the ECG signal, X i,b represents the b-th category indicator data of the i-th sampling point, X j,b Represents the b-th category indicator data of the j-th sampling point.

[0089] It is used to represent the proportion of the negative correlation normalized value of ST-T of the j-th sampling point in the overall distribution of the negative correlation normalized values ​​of ST-T of all sampling points. i,b -X j,b | represents the difference between the b-type indicator data at the i-th sampling point and the j-th sampling point. The greater the proportion of the negatively correlated normalized value of ST-T at each sampling point in the overall distribution of the negatively correlated normalized values ​​of ST-T at all sampling points, and the greater the difference between the b-type indicator data at the i-th sampling point and the other sampling points, the greater the abnormality of the b-type indicator at the i-th sampling point.

[0090] By using the above method, the heart rate abnormality and blood pressure abnormality of each sampling point on the electrocardiogram signal can be obtained.

[0091] The following description continues with a single sampling point as an example. For any sampling point, a myocardial ischemia index corresponding to the sampling point is obtained based on the heart rate abnormality degree and the blood oxygen saturation standard degree at the sampling point. Both the heart rate abnormality degree and the blood oxygen saturation standard degree are positively correlated with the myocardial ischemia index. In this embodiment, the product of the heart rate abnormality degree and the blood oxygen saturation standard degree is used as the myocardial ischemia index corresponding to the sampling point. The greater the heart rate abnormality degree and the blood oxygen saturation standard degree at the sampling point, the greater the myocardial ischemia index corresponding to the sampling point.

[0092] By using the above method, the myocardial ischemia index corresponding to each sampling point on the electrocardiogram signal can be obtained.

[0093] Step S4, comprehensively analyzing the difference between the heart rate abnormality and the blood pressure abnormality at each sampling point and the myocardial ischemia index to obtain a myocardial ischemia evaluation value; and determining whether to issue an early warning through the smart early warning bracelet worn by the person to be tested based on the myocardial ischemia evaluation value.

[0094] In patients with coronary heart disease, abnormal heart rate and blood pressure often occur simultaneously when myocardial ischemia occurs. First, myocardial ischemia triggers the activation of the sympathetic nervous system, leading to increased adrenaline secretion, which accelerates the heart rate (tachycardia) and triggers vasoconstriction, resulting in increased peripheral vascular resistance, which in turn increases blood pressure. Second, myocardial ischemia leads to weakened cardiac pumping function and insufficient cardiac output, which may cause a drop in blood pressure, especially when the ischemia is severe or heart function is significantly impaired. In addition, electrophysiological changes in the ischemic area may lead to arrhythmias, further affecting the stability of heart rate and blood pressure. The imbalance of sympathetic and parasympathetic nerves, changes in vascular reactivity, and increased cardiac burden work together to make abnormal heart rate and blood pressure often occur simultaneously, forming a complex cardiovascular reaction.

[0095] From the above characteristics, it can be seen that for each sampling point preliminarily determined to be consistent with myocardial ischemia in patients with coronary heart disease under ST-T characteristics based on abnormal heart rate, if the abnormal heart rate is accompanied by abnormal blood pressure, the ST-T characteristics should be more consistent with myocardial ischemia in patients with coronary heart disease.

[0096] Next, this embodiment is described by still taking a sampling point on an electrocardiogram signal as an example.

[0097] For any sampling point, the difference between the heart rate abnormality and the blood pressure abnormality at that sampling point is calculated and recorded as a second difference. A myocardial ischemia assessment value for that sampling point is obtained based on the second difference and the myocardial ischemia index corresponding to that sampling point. The second difference is negatively correlated with the myocardial ischemia assessment value, while the myocardial ischemia index is positively correlated with the myocardial ischemia assessment value. In this embodiment, the myocardial ischemia assessment value for that sampling point is determined by multiplying the negatively correlated normalized value of the second difference by the myocardial ischemia index corresponding to that sampling point.

[0098] In this embodiment, a specific calculation formula for the myocardial ischemia evaluation value is given. The myocardial ischemia evaluation value corresponding to the i-th sampling point can be expressed as:

[0099] Q i =exp(-|C i ′ -C i ″|)×G i′

[0100] Among them, Q i represents the myocardial ischemia evaluation value corresponding to the i-th sampling point, C i ′ Indicates the abnormality of heart rate at the i-th sampling point, C i ″ represents the blood pressure abnormality of the i-th sampling point, G i ′ represents the myocardial ischemia index corresponding to the i-th sampling point, exp() represents the exponential function with a natural constant as the base, and || represents the absolute value sign.

[0101] |C i ′ -C i "|" represents the second difference corresponding to the i-th sampling point, which is used to reflect the difference between the heart rate abnormality and the blood pressure abnormality at the i-th sampling point. When the second difference corresponding to the i-th sampling point is smaller and the heart rate abnormality at the i-th sampling point is greater, the myocardial ischemia evaluation value corresponding to the i-th sampling point is greater.

[0102] By using the above method, the myocardial ischemia evaluation value corresponding to each sampling point on the electrocardiogram signal can be obtained.

[0103] The total number of sampling points on the electrocardiogram signal whose myocardial ischemia evaluation value is greater than the preset evaluation threshold is counted. If the total number is greater than the preset number, an early warning is issued; if the total number is less than or equal to the preset number, no early warning is issued. The system determines whether the patient has myocardial ischemia by analyzing whether there is ST segment elevation or T wave change in the electrocardiogram signal, and ensuring that all sampling points within the change meet the myocardial ischemia of coronary heart disease patients under the ST-T characteristics. Finally, the system will generate an early warning message and provide timely feedback through the smart bracelet to remind the wearer or relevant personnel to ensure that the relevant personnel can take necessary countermeasures in time. In this embodiment, the preset evaluation threshold is 0.8. In specific applications, the implementer can set it according to the specific situation; the preset number implementer sets it according to the acquisition time of the electrocardiogram signal and the data acquisition frequency, which will not be elaborated here.

[0104] The method provided in this embodiment optimizes the reduction of false alarms, avoiding interference from diseases that may cause similar ST-T changes, such as cardiomyopathy, myocarditis, valvular disease, pericarditis, and cerebrovascular accidents (especially intracranial hemorrhage). Furthermore, it reduces interference from electrolyte disorders such as hypokalemia and hyperkalemia, certain medications (such as digitalis and quinidine), and autonomic nervous system disorders that may also cause ST-T changes. Ventricular hypertrophy, bundle branch block, and pre-excitation syndrome can also lead to secondary ST-T changes. By identifying and eliminating these interfering factors, the smart bracelet can ensure more accurate early warning.

[0105] In view of the problem that the existing technology is difficult to distinguish ST-T changes caused by myocardial ischemia in patients with coronary heart disease from those caused by other reasons, thereby resulting in low credibility of early warning of myocardial ischemia in patients with coronary heart disease, this embodiment takes into account the symmetry of the peak points of ST-T changes, and can judge whether the peak point shows ST-T characteristics based on this characteristic. If the peak point shows ST-T characteristics and the sampling point is symmetrical about the peak point, then the sampling point also has ST-T characteristics; therefore, the symmetry of the amplitude of the sampling points in the neighborhood of the peak point closest to each sampling point on the electrocardiogram signal, as well as the consistency of the tilt change of each sampling point and the peak point closest to it are evaluated. A comprehensive analysis was conducted to evaluate the ST-T characteristics of each sampling point. However, other factors may also cause ST-T characteristics, so it is necessary to further verify whether these sampling points meet the characteristics of myocardial ischemia in patients with coronary heart disease. To this end, the blood oxygen saturation data was first combined to determine the blood oxygen saturation standard of each sampling point. Further combined with abnormal heart rate and the abnormal relationship between blood pressure and heart rate, it was finally determined that each sampling point met the myocardial ischemia degree of patients with coronary heart disease under ST-T characteristics conditions, and the myocardial ischemia evaluation value was obtained. Then, it was determined whether an early warning should be issued through the smart early warning bracelet worn by the person to be tested, thereby improving the credibility of the early warning results.

[0106] It should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A real-time monitoring and intelligent early warning wristband for myocardial ischemia in patients with coronary heart disease, comprising a memory and a processor, characterized in that: The processor executes the computer program stored in the memory to implement the following steps: Obtaining electrocardiogram signals and different indicator data of the person to be tested, wherein the indicator data includes blood oxygen saturation data, heart rate data and blood pressure data; Obtaining the ST-T characteristic of each sampling point based on the symmetry of the amplitudes of the sampling points in the neighborhood of the peak point closest to each sampling point on the electrocardiogram signal and the consistency of the tilt changes of each sampling point and the peak point closest to it; and determining the blood oxygen saturation standard of each sampling point by combining the ST-T characteristic and the corresponding blood oxygen saturation data; Based on the difference in ST-T characteristics between each sampling point and other sampling points and the difference in similar indicator data, the abnormality of each type of indicator at each sampling point is evaluated; combined with the heart rate abnormality and blood oxygen saturation standard of each sampling point, the myocardial ischemia index corresponding to each sampling point is obtained; The myocardial ischemia evaluation value is obtained by combining the difference in the heart rate abnormality and the blood pressure abnormality at each sampling point with the myocardial ischemia index; Based on the myocardial ischemia evaluation value, it is determined whether to issue an early warning through the smart early warning bracelet worn by the person to be tested.

2. A real-time monitoring and intelligent early warning wristband for myocardial ischemia in patients with coronary heart disease according to claim 1, characterized in that: The ST-T property of each sampling point is obtained based on the symmetry of the amplitudes of the sampling points in the neighborhood of the peak point closest to each sampling point on the electrocardiogram signal, and the consistency of the tilt changes of each sampling point and the peak point closest to it, including: For any peak point on the electrocardiogram signal: obtaining a symmetry factor of the peak point according to the symmetry of the amplitudes of the sampling points on the left and right sides of the peak point in the neighborhood of the peak point; For any sampling point on the electrocardiogram signal: the ST-T characteristic of the any sampling point is obtained based on the slope difference between the any sampling point and the peak point closest to the any sampling point, and the symmetry factor of the peak point closest to the any sampling point, wherein the slope difference is negatively correlated with the ST-T characteristic, and the symmetry factor is positively correlated with the ST-T characteristic.

3. A real-time monitoring and intelligent early warning wristband for myocardial ischemia in patients with coronary heart disease according to claim 2, characterized in that: The obtaining the symmetry factor of any peak point according to the symmetry of the amplitudes of the sampling points on the left and right sides of any peak point in the neighborhood of the any peak point includes: Calculate the amplitude difference between two sampling points with the same time interval as the peak point in the neighborhood of the peak point respectively; The symmetry factor of any peak point is obtained according to the sum of all the amplitude differences in the neighborhood of any peak point, and the sum is negatively correlated with the symmetry factor.

4. A wristband for real-time monitoring and intelligent early warning of myocardial ischemia in patients with coronary heart disease according to claim 1, characterized in that: Determining the blood oxygen saturation standard of each sampling point by combining the ST-T property and the corresponding blood oxygen saturation data includes: For any sampling point, a first difference between the blood oxygen saturation data of the any sampling point and a preset value is calculated; and the product of the negative correlation normalization result of the first difference and the ST-T characteristic of the any sampling point is determined as the blood oxygen saturation standard of the any sampling point.

5. The real-time monitoring and intelligent early warning wristband for myocardial ischemia in patients with coronary heart disease according to claim 1, characterized in that: The abnormality of each type of indicator at each sampling point is evaluated based on the difference in ST-T between each sampling point and other sampling points and the difference in similar indicator data, including: For any sampling point: The abnormality degree of each type of indicator at any sampling point is obtained based on the numerical proportion of the negative correlation normalized value of the ST-T characteristic at each sampling point on the electrocardiogram signal in the overall distribution of the negative correlation normalized value of the ST-T characteristic at all sampling points, and the difference between each type of indicator data at any sampling point and all sampling points. The numerical proportion and the difference between each type of indicator data are both positively correlated with the abnormality degree.

6. A real-time monitoring and intelligent early warning wristband for myocardial ischemia in patients with coronary heart disease according to claim 5, characterized in that: Obtaining the numerical proportion of the negative correlation normalized value of the ST-T characteristic at each sampling point on the electrocardiogram signal in the overall distribution of the negative correlation normalized values ​​of the ST-T characteristic at all sampling points includes: Calculate the cumulative sum of the negative correlation normalized values ​​of ST-T of all sampling points; The ratio of the negative correlation normalized value of the ST-T property of each sampling point to the cumulative sum is used as the numerical ratio corresponding to each sampling point.

7. The real-time monitoring and intelligent early warning wristband for myocardial ischemia in patients with coronary heart disease according to claim 1, characterized in that: The myocardial ischemia index corresponding to each sampling point is obtained by combining the heart rate abnormality and the blood oxygen saturation standard of each sampling point, including: For any sampling point: A myocardial ischemia index corresponding to any sampling point is obtained according to the heart rate abnormality degree of any sampling point and the blood oxygen saturation standard degree of any sampling point, and both the heart rate abnormality degree and the blood oxygen saturation standard degree are positively correlated with the myocardial ischemia index.

8. The real-time monitoring and intelligent early warning wristband for myocardial ischemia in patients with coronary heart disease according to claim 1, characterized in that: The myocardial ischemia evaluation value is obtained by integrating the difference between the heart rate abnormality and the blood pressure abnormality at each sampling point and the myocardial ischemia index, including: For any sampling point: calculating a second difference between the heart rate abnormality degree and the blood pressure abnormality degree at any of the sampling points; A myocardial ischemia evaluation value of any sampling point is obtained based on the second difference and the myocardial ischemia index corresponding to any sampling point, wherein the second difference is negatively correlated with the myocardial ischemia evaluation value, and the myocardial ischemia index is positively correlated with the myocardial ischemia evaluation value.

9. A real-time monitoring and intelligent early warning wristband for myocardial ischemia in patients with coronary heart disease according to claim 8, characterized in that: Obtaining a myocardial ischemia evaluation value of any sampling point according to the second difference and the myocardial ischemia index corresponding to any sampling point includes: The product of the negative correlation normalized value of the second difference and the myocardial ischemia index corresponding to any one of the sampling points is used as the myocardial ischemia evaluation value of any one of the sampling points.

10. The real-time monitoring and intelligent early warning wristband for myocardial ischemia in patients with coronary heart disease according to claim 1, characterized in that: The method of judging whether to issue an early warning through the smart early warning bracelet worn by the person to be tested based on the myocardial ischemia evaluation value includes: If the total number of sampling points with myocardial ischemia evaluation values ​​greater than the preset evaluation threshold is greater than the preset number, an early warning will be issued through the smart early warning bracelet worn by the person to be tested; If the total number of sampling points whose myocardial ischemia evaluation values ​​are greater than the preset evaluation threshold is less than or equal to the preset number, no warning is issued.

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