TW202245693A - Myocardial ischemia detection device and myocardial ischemia detection method detect the position of myocardial ischemia of human body by calculating feature values during QT interval - Google Patents

Abstract

A myocardial ischemia detection device comprises a measuring unit and a processing unit. A myocardial ischemia detection method comprises steps of a measurement step, a feature capturing step, and a first analysis step. The measurement step is configured to obtain several electrocardiography signals of a human body through the measuring unit. The position for measuring the at least portion of electrocardiography signals corresponds to the left chest of the human body. The feature capturing step is configured to capture QT interval of each electrocardiography signal through the processing unit and calculates several feature values respectively corresponding to several point positions of the human body. The first analysis step is configured to compare with the point position corresponding to at least one of the lowest in the feature value to detect the position of myocardial ischemia. In comparison with the existing analysis methods of waveform change at the ST segment, the QT interval may not be interfered with noise and baseline shift and the evaluation error can be avoided.

Description

Myocardial ischemia detection device and myocardial ischemia detection method

The invention relates to an analysis of electrocardiographic signals, in particular to a myocardial ischemia detection device and a myocardial ischemia detection method.

The three coronary arteries that maintain blood supply to the heart are the right coronary artery (RCA), the left anterior descending coronary artery (LAD), and the left recurrent coronary artery (LCX). According to different arterial blockages, the medical treatments are different. The American Heart Association stipulates that patients with myocardial infarction should receive cardiac catheterization within 90 minutes after arriving at the hospital to reduce the time and mortality of myocardial ischemia. Therefore, how to evaluate whether there is myocardial ischemia and myocardial ischemia in the shortest time Location is quite important.

Generally, when evaluating the location of acute myocardial ischemia, a twelve-lead electrocardiogram is used for evaluation. During the evaluation, medical personnel need to base the lead of different groups such as anterior chest lead (V1-V6), inferior wall lead (II, III, aVF), and lateral wall/apical lead (I, aVL, V5, V6). In the early stage of myocardial ischemia, the change of ST segment is often not obvious, so it is difficult to shorten the evaluation time in practice.

In addition, the waveform changes of the ST segment of the electrocardiogram are easily affected by chest wall impedance, noise, and baseline shift, and thus are prone to evaluation errors.

Therefore, the object of the present invention is to provide a myocardial ischemia detection device that can overcome at least one of the disadvantages of the prior art.

Another object of the present invention is to provide a method for detecting myocardial ischemia that can overcome at least one disadvantage of the prior art.

Therefore, the myocardial ischemia detection device of the present invention is applicable to a human body. The myocardial ischemia detection device includes a measurement unit and a processing unit.

The measurement unit includes four limb electrodes and several chest electrodes. The limb electrodes and the chest electrodes are suitable for obtaining several electrocardiographic signals of the human body. The measurement positions of at least part of the chest electrodes correspond to the left chest of the human body.

The processing unit is connected to the measurement unit and can receive the ECG signals. The processing unit can extract the QT intervals of the ECG signals, and use the QT intervals to calculate several eigenvalues corresponding to several points on the left chest of the human body, and then according to the eigenvalues The ECG signal measurement position corresponding to at least one of the lowest ones is used to detect the myocardial ischemia position of the human body.

The myocardial ischemia detection method of the present invention includes a measurement step, a feature extraction step, and a first analysis step.

The measurement step is to obtain several ECG signals of a human body. The measuring positions of at least part of the ECG signals correspond to the left chest of the human body.

In the feature extraction step, a processing unit extracts the QT interval of each ECG signal, and calculates several feature values respectively corresponding to several points of the left chest of the human body according to the QT interval.

The first analyzing step is to compare the point corresponding to at least one of the lowest characteristic values to the position of the left chest of the human body, so as to detect the myocardial ischemia position.

The efficacy of the present invention lies in: by calculating the characteristic values with the QT intervals to detect the myocardial ischemia position of the human body, since the QT intervals are shorter than the existing analysis method based on the waveform change of the ST segment Unaffected by chest wall impedance, noise, and baseline offset, evaluation errors can be avoided.

Referring to FIG. 1 to FIG. 4 , an embodiment of the myocardial ischemia detection device of the present invention is applicable to a human body 1 . The human body includes a pair of reference planes 100 corresponding to the left chest. The reference plane 100 is composed of a right sternal margin 11 of the human body 1, a first intercostal horizontal line 12 corresponding to the height of the right sternal margin 11, a left underarm midline 13, and an eighth rib corresponding to the right sternum Delimited by the horizontal line 14 at the height of the edge 11.

The myocardial ischemia detection device includes a measurement unit 2 , a processing unit 3 , a database unit 4 , an input unit 5 , an output unit 6 , and a wearable unit 7 . The processing unit 3 is signally connected to the measurement unit 2 , the processing unit 3 , the database unit 4 , the input unit 5 , and the output unit 6 .

The input unit 5 can be input with an operation instruction, a mode selection instruction, and an output instruction.

The measurement unit 2 includes four limb conductive electrodes 26 and several chest electrodes 21 suitable for being arranged on the reference surface 100 and spaced apart from each other. The measurement unit 2 can make the limb conductive electrodes 26 and the chest electrodes 21 obtain several ECG signals of the human body 1 according to the operation instruction. The measuring positions of at least part of the chest electrodes 21 correspond to the left chest of the human body 1 . Each ECG signal has P wave, Q wave, R wave, S wave and T wave.

Among them, it should be particularly noted that, in order to clearly disclose the installation positions of the chest electrodes 21 and the wearing unit 7 corresponding to the human body 1, in FIG. 3 and the subsequent FIG. 10, FIG. The front electrode 21 is drawn in phantom lines, while the wearable unit 7 of FIG. 2 is drawn in dotted lines.

The number of the chest electrodes 21 can be more than 16, and the corresponding number of electrocardiographic signals of the reference surface 100 of the human body 1 are obtained through the chest electrodes 21, and the electrocardiographic signals correspond to the measurement positions It is arranged on the reference plane 100 .

In terms of the lateral positions of the chest electrodes 21 corresponding to the human body 1, at least 2 chest electrodes 21 of the chest electrodes 21 correspond to the right sternal border 11, and at least 3 chest electrodes 21 correspond to the left The sternal border 111, at least 3 chest electrodes 21 correspond to the midline 113 between the left sternal border 111 and a left clavicle midline 112, at least 4 chest electrodes 21 correspond to the left clavicle midline 112, at least 2 The chest electrodes 21 correspond to a left axillary anterior edge line 114 , and at least two chest electrodes 21 correspond to the left axillary midline 13 .

In terms of the longitudinal positions of the chest electrodes 21 corresponding to the human body 1, at least 3 chest electrodes 21 of the chest electrodes 21 correspond to a third intercostal space corresponding to the height of the right sternal margin 11, at least 5 chest The front electrode 21 corresponds to a fourth intercostal space corresponding to the height of the right sternal border 11, at least 4 front electrodes 21 correspond to a fifth intercostal space corresponding to the height of the right sternal border 11, and at least one front electrode 21 corresponds to a sixth intercostal space Corresponding to the height of the right sternal border 11, and corresponding to the midline 113 between the left sternal border 111 and the left clavicle midline 112, the heights of at least three of the chest electrodes 21 are between the third intercostal space to between the sixth rib.

In this embodiment, the number of the chest electrodes 21 is 16, and in terms of the lateral positions of the chest electrodes 21 corresponding to the human body 1, two chest electrodes 21 in the chest electrodes 21 Corresponding to the right sternal border 11, three front electrodes 21 correspond to the left sternal border 111, three front electrodes 21 correspond to the midline 113 between the left sternal border 111 and the left clavicle midline 112, and four chest electrodes. The front electrode 21 corresponds to the left clavicle midline 112, the two chest electrodes 21 correspond to the left underarm front edge line 114, and the two chest electrodes 21 correspond to the left underarm midline 13; Corresponding to the longitudinal position of the human body 1, among the chest electrodes 21, three chest electrodes 21 correspond to the height of the right sternal border 11 in the third intercostal space, and five chest electrodes 21 correspond to the fourth intercostal space. At the height of the right sternal border 11, the 4 chest electrodes 21 correspond to the fifth intercostal space corresponding to the height of the right sternal border 11, the 4 chest electrodes 21 correspond to the sixth intercostal space corresponding to the height of the right sternal border 11, and correspond to The three chest electrodes 21 located on the midline 113 between the left sternal margin 111 and the left clavicle midline 112 correspond to the heights of a fourth rib, a fifth rib, and a sixth rib, respectively.

In this embodiment, the measurement unit 2 also includes a signal buffer 22 electrically connected to the chest electrodes 21, a signal amplifier 23 electrically connected to the signal buffer 22, a filter electrically connected to the signal amplifier 23 24, and a signal converter 25 electrically connected to the filter 24. The signal buffer 22 can provide a sufficiently large input impedance to couple the electrocardiographic signals to the signal amplifier 23, and the signal amplifier 23 further amplifies the electrocardiographic signals and inputs the filter 24, and the filter 24 can The noise of the ECG signal and the interference of the power signal are removed, and the signal converter 25 can convert the ECG signal into an analog signal for subsequent analysis by the processing unit 3 .

The database unit 4 stores comparison information 41 . The comparison information 41 is divided into three comparison areas 411 from the upper right to the lower left, and the comparison areas 411 represent the left recurrent coronary artery (LCX), the left anterior descending coronary artery (LAD), and Right coronary artery (RCA).

The processing unit 3 is connected to the measurement unit 2 and can receive the ECG signals. The processing unit 3 can extract the QT interval and the RR interval of the ECG signals, and calculate several reference planes respectively corresponding to the left chest of the human body 1 through the QT interval and the RR interval The eigenvalues of several points of 100. The characteristic values are calculated based on the ECG signals and the QTc intervals corresponding to the corresponding points.

The calculation method of these characteristic values is to calculate the QTc interval of the ECG signal by the QT interval and the RR interval, and then decide whether to use two-dimensional The interpolation calculation expands and calculates the QTc interval of more points, and uses the QTc interval calculated from the ECG signals and the QTc interval calculated by the expansion as the feature values respectively.

In this embodiment, the processing unit 3 extracts the QT intervals and RR intervals of the above-mentioned 16 ECG signals, and calculates 16 QTc intervals respectively based on the QT intervals and the RR intervals, and then The QTc interval extended to 24 points is calculated through two-dimensional interpolation. Wherein, the calculation formula for calculating the QTc interval of the electrocardiographic signal based on the QT interval and the RR interval is:

Among them, QTc is the QTc interval, QT is the QT interval (in milliseconds), and RR is the RR interval (in seconds).

The processing unit 3 can detect the location of myocardial ischemia in the human body 1 according to the ECG signal measurement position corresponding to at least one of the lowest characteristic values, and can detect the myocardial ischemia position of the human body 1 according to the distribution state of the characteristic values and the The comparison information 41 is compared to detect the range of myocardial ischemia, and the detection result of the location of myocardial ischemia and the range of myocardial ischemia can be output to the output unit 6 according to the output command.

The processing unit 3 can also display the characteristic values on the output unit 6 according to the output instruction, and can also image the numerical differences and corresponding distribution positions of the characteristic values on the output unit 6 with different color scales . Wherein, the manner in which the processing unit 3 images the numerical differences of these feature values and the corresponding distribution positions in different color scales is similar to the layered coloring method and the topographic color shading method used in cartography, that is, Different colors or shades are used to represent different characteristic values, so that a user can easily and conveniently understand the distribution of the characteristic values, so as to facilitate the evaluation of myocardial ischemia location and myocardial ischemia range.

In addition, the processing unit 3 can calculate and evaluate the severity of overall myocardial ischemia in at least one of a first evaluation mode and a second evaluation mode according to the mode selection instruction of the input unit 5, and according to the output The instruction outputs the evaluation result to the output unit 6 .

），並依據該離散參數評估該人體1的整體心肌缺血的嚴重程度。該評估參數演算法為： The first evaluation mode is an evaluation parameter algorithm to calculate a discrete parameter (

), and evaluate the severity of the overall myocardial ischemia of the human body 1 according to the discrete parameter. The evaluation parameter algorithm is:

為該離散參數，S為該等點位的總數量，

為一特定點位的QTc間期，n為最接近該特定點位對應於該人體1位置的點位數目，

為其中一個最接近該特定點位對應於該人體1位置的點位的QTc間期。當

值越大，代表該人體1的整體心肌缺血的嚴重程度越嚴重。 in,

is the discrete parameter, S is the total number of such points,

is the QTc interval of a specific point, n is the number of points closest to the specific point corresponding to the position of the human body 1,

is the QTc interval of one of the points closest to the specific point corresponding to the position of the human body 1 . when

The larger the value, the more severe the overall myocardial ischemia of the human body 1 is.

The second evaluation mode is to calculate the difference QTcD between the maximum value and the minimum value of the QTc interval at the points, and evaluate the human body according to the difference QTcD between the maximum value and the minimum value of the QTc interval 1 The severity of the overall myocardial ischemia. When the difference QTcD between the maximum value and the minimum value of the QTc interval is greater, it means that the overall myocardial ischemia of the human body 1 is more severe.

The wearing unit 7 can be worn by the human body 1 , and the chest electrodes 21 of the measuring unit 2 are disposed on the wearing unit 7 . When the human body 1 wears the wearing unit 7 , the chest electrodes 21 respectively correspond to predetermined positions of the reference plane 100 . In this embodiment, the wearing unit 7 is a vest-like coat.

Referring to FIG. 1 to FIG. 4 , in actual application, it can be detected with a myocardial ischemia detection method, which includes the following steps S1 to S5.

Step S1 , input command step: input the operation command, the mode selection command, and the output command into the input unit 5 .

Step S2, measuring step: obtaining the ECG signals of the human body 1 .

Wherein, at least part of the measurement positions of the ECG signals correspond to the left chest of the human body 1 .

Wherein, the measuring step is to obtain the ECG signals of a reference surface 100 of the human body 1 . The reference plane 100 is composed of the right sternal border 11 of the human body 1, the horizontal line 12 corresponding to the height of the right sternal border 11 between the first intercostals, the left underarm midline 13, and the eighth rib corresponding to the right sternal Delimited by the horizontal line 14 at the height of the edge 11.

Step S3, feature extraction step: the processing unit 3 extracts the QT interval and RR interval of each ECG signal, and calculates several corresponding to the human body 1 according to the QT interval and the RR interval The eigenvalues of several points on the left chest of the patient.

In this embodiment, the feature values calculated in the feature extraction step are calculated based on the ECG signals to calculate the QTc interval corresponding to the corresponding points.

Step S4, the first analysis step: comparing the point corresponding to at least one of the lowest eigenvalues to the position of the left chest of the human body to detect the location of myocardial ischemia, and comparing the points corresponding to the lowest one of the eigenvalues The high-low distribution state is compared with the comparison information 41 to detect the range of myocardial ischemia.

Wherein, the first analysis step can be automatically processed by the processing unit 3 to detect the myocardial ischemia location and the myocardial ischemia range of the human body 1, and then output the detection result to the output unit 6 according to the output instruction. In the first analysis step, the processing unit 3 can firstly compare the feature values to the position corresponding to the left chest of the human body 1 and represent the level of the feature values in different color scales according to the output instruction. After the output unit 6 generates the corresponding image, the user visually evaluates the distribution of the characteristic values, and the user detects the location of myocardial ischemia and myocardial ischemia by comparing the image with the comparison information 41. range of blood.

Step S5, second analysis step: the processing unit 3 calculates and evaluates the overall myocardial ischemia of the human body 1 in at least one of the first evaluation mode and the second evaluation mode according to the mode selection instruction of the input unit 5 The severity of the blood, and output the evaluation result to the output unit 6 according to the output instruction.

Through the above steps S1 to S5, the location of myocardial ischemia, the extent of myocardial ischemia, and the severity of the overall myocardial ischemia of the human body 1 can be evaluated.

Referring to the following Table 1 and Fig. 4 and Fig. 6, for example, Table 1 is a QTc interval distribution table, which uses the myocardial ischemia detection device and the myocardial ischemia detection method to take 16 such chest Electrode 21 is used to obtain 16 ECG signals obtained from the left chest of a patient with left recurrent coronary artery (LCX) stenosis. Get a QTc interval distribution table with a total of 24 points (including the aforementioned 16 QTc intervals calculated from ECG signals). The measurement positions and the point positions corresponding to the two-dimensional interpolation are arranged, and FIG. 6 is an image output to the output unit 6 representing the level of the feature values with different color levels.

It can be seen from Table 1 and Figure 6 that the lowest one of the QTc intervals corresponds to the upper right in the figure, and then refer to the comparison information 41 in Figure 4 to evaluate the myocardial ischemia location of the patient It is located in the blood supply area of the left recurrent coronary artery (LCX).

It should be noted that the QTc interval of the above-mentioned 24 points can also obtain the ECG signal through 17, 18 or other numbers of the chest electrodes 21, and then obtain 24 points through the calculation program of two-dimensional interpolation The QTc interval of the position, or can also be calculated directly through the ECG signals obtained by 24 such chest electrodes 21, without the need for a two-dimensional interpolation calculation program, and the points of the QTc interval distribution table The number of bits can also be other numbers. For example, the ECG signals obtained by 24 such chest electrodes 21 can be expanded into a 36-point QTc interval distribution table by two-dimensional interpolation calculation.

Table 1 Example of QTc interval in patients with left recurrent coronary artery (LCX) stenosis 426 409 400 392 377 368 426 405 396 383 362 358 411 396 388 366 451 451 411 404 386 366 409 430

Refer to Table 2, Figure 4, and Figure 7 below. Table 2 uses the myocardial ischemia detection device and the myocardial ischemia detection method to detect a right coronary artery (RCA) stenosis with 16 such front electrodes 21. After calculating the QTc intervals of the 16 ECG signals obtained from the patient's left chest, a QTc interval distribution table with a total of 24 points (including the aforementioned 16 QTc intervals calculated from ECG signals), and FIG. 7 is the corresponding image displayed on the output unit 6 .

From Table 2 and Figure 7, it can be known that the lowest one of the QTc intervals corresponds to the left side of the figure, and with reference to the comparison information 41 in Figure 4, it can be estimated that the patient's myocardial ischemia location is Located in the territory supplied by the right coronary artery (RCA).

Table 2 Examples of QTc intervals in patients with right coronary artery (RCA) stenosis 417 428 356 390 400 404 428 348 390 394 409 409 394 360 398 394 409 413 394 377 392 402 405 409

Refer to Table 3, Figure 4, and Figure 8 below. Table 3 uses the myocardial ischemia detection device and the myocardial ischemia detection method to measure the stenosis of a left anterior descending coronary artery (LAD) with 16 such chest electrodes 21. After calculating the QTc intervals of the 16 ECG signals obtained from the patient's left chest, a QTc interval distribution table with a total of 24 points (including The aforementioned 16 QTc intervals calculated from ECG signals), and FIG. 8 is the corresponding image displayed on the output unit 6 .

It can be known from Table 3 and Figure 8 that the lowest one of the QTc intervals corresponds to the upper middle area in the figure, and then refer to the comparison information 41 in Figure 4 to evaluate the patient's myocardial The ischemic site is located in the blood supply area of the left anterior descending coronary artery (LAD).

Table 3 Examples of QTc intervals in patients with left anterior descending coronary artery (LAD) stenosis 415 374 378 378 388 393 415 399 382 382 399 399 403 390 403 403 403 399 403 397 402 407 405 402

Refer to the following Table 4 and Fig. 4 and Fig. 9, Table 4 is the use of the myocardial ischemia detection device and the myocardial ischemia detection method, with 16 such chest electrodes 21 pairs of one three coronary artery stenosis (3VD) After calculating the QTc intervals of the 16 ECG signals obtained from the patient's left chest, a QTc interval distribution table with a total of 24 points (including The aforementioned 16 QTc intervals calculated from ECG signals), and FIG. 9 is the corresponding image displayed on the output unit 6 .

It can be known from Table 4 and Figure 9 that the lowest one of the QTc intervals corresponds to the upper left area in the figure, but according to Figure 9, the area with a low QTc interval includes the upper left and the upper left area in the figure. In conjunction with the comparison information 41 in Figure 4, the area with a low QTc interval covers the three comparison areas 411 of the comparison information 41, so the extent of myocardial ischemia in this patient can be evaluated Covers the territory supplied by the three coronary arteries (3VD).

Table 4 Examples of QTc intervals in patients with three coronary artery stenosis (3VD) 376 364 442 417 411 400 364 458 430 417 405 389 401 438 422 417 422 422 401 419 423 430 426 424

The above-mentioned Tables 1 to 4 and Figures 6 to 9 detect myocardial ischemia with 16 ECG signals, but are not limited thereto. The myocardial ischemia detection device and the myocardial ischemia detection method can also be applied to different numbers of The chest electrodes 21 and different numbers of ECG signals can also be evaluated with QTc interval distribution tables with different numbers of points. For example, the following Tables 5 to 8 and Figures 11 to 14 are sequentially For the above-mentioned Table 1 to Table 4 and the above-mentioned Fig. 6 to Fig. 9 patients, obtain 24 ECG signals with 24 such chest electrodes 21 as shown in Fig. 10, after calculating the QTc interval of these ECG signals , and then obtain a QTc interval distribution table of 36 points in total (including the aforementioned 24 QTc intervals calculated from ECG signals) through two-dimensional interpolation calculations and the corresponding images displayed on the output unit 6 .

Wherein, in terms of the lateral positions of the chest electrodes 21 corresponding to the human body 1, the 4 chest electrodes 21 in the chest electrodes 21 correspond to the right sternal border 11, and the 5 chest electrodes 21 correspond to the left side. The sternal border 111 and the 4 chest electrodes 21 correspond to the midline 113 between the left sternal border 111 and the left clavicle midline 112, and the 4 chest electrodes 21 correspond to the left clavicle midline 112 and 4 chest electrodes 21 corresponds to the left underarm front edge line 114, and the three chest electrodes 21 correspond to the left underarm midline 13; in terms of the longitudinal positions of the chest electrodes 21 corresponding to the human body 1, the chest electrodes 21 2 chest electrodes 21 correspond to the height of the right sternal border 11 in the first intercostal space, 3 chest electrodes 21 correspond to the height of the right sternal border 11 in the second intercostal space, and 5 chest electrodes 21 correspond to the height of the right sternal border 11. The third intercostal space corresponds to the height of the right sternal margin 11, the 6 chest electrodes 21 correspond to the fourth intercostal space corresponding to the height of the right sternal margin 11, and the 5 chest electrodes 21 correspond to the fifth intercostal space corresponding to the right sternal margin 11 Height, three chest electrodes 21 correspond to the sixth intercostal space and correspond to the height of the right sternal border 11 .

大於9.4毫秒（msec）或 QTcD大於66毫秒（msec）時，即代表有顯著的心肌缺血，可能需要進行較積極的治療。 After comparing the above Tables 1 to 4 and the above Figures 6 to 9, and the following Tables 5 to 8 and Figures 11 to 14, it can be found that for the same patient no matter whether the 16 ECG signals (see Figure 3; QTc interval distribution table of 24 points) or 24 ECG signals (see Figure 10; QTc interval distribution table of 36 points) can be calculated and analyzed, and can be obtained when analyzing the location and range of myocardial ischemia Consistent analysis results, and in some cases, the analysis of 24 ECG signals (QTc interval distribution table with 36 points) can more clearly show the area with low QTc interval (for example: Fig. 14 Compared with Fig. 9, it can be clearly seen that the area with low QTc interval covers the three comparison areas 411 of the comparison information 41). In the present embodiment where 24 ECG signals are analyzed (the QTc interval distribution table with a total of 36 points is obtained through two-dimensional interpolation calculation), if

When it is greater than 9.4 milliseconds (msec) or QTcD is greater than 66 milliseconds (msec), it means that there is significant myocardial ischemia, and more aggressive treatment may be required.

Table 5 Examples of QTc intervals in patients with left recurrent coronary artery (LCX) stenosis 426 422 413 413 413 413 426 413 405 403 401 407 426 409 400 392 388 384 426 405 396 383 362 358 411 396 388 366 451 451 411 404 386 366 447 449

Table 6 Examples of QTc intervals in patients with right coronary artery (RCA) stenosis 398 398 411 411 411 411 413 417 425 409 408 410 417 428 356 390 405 408 428 348 390 394 409 409 394 360 398 394 409 413 394 377 392 402 398 405

Table 7 Examples of QTc intervals in patients with left anterior descending coronary artery (LAD) stenosis 395 370 372 372 372 372 395 336 374 374 380 376 415 374 378 378 395 390 415 399 382 382 399 399 403 390 403 403 403 399 403 397 402 407 403 401

Table 8 Examples of QTc intervals in patients with three coronary artery stenosis (3VD) 413 422 391 391 391 391 385 372 360 389 394 392 376 364 442 417 401 394 364 458 430 417 405 389 401 438 422 417 422 422 401 419 424 430 430 426

值或該等QTc間期的最大值與最小值的差距值QTcD越大，代表該人體1的整體心肌缺血的嚴重程度越嚴重。 When assessing the severity of the overall myocardial ischemia, whether the first evaluation mode or the second evaluation mode is used, the main principle is to calculate the dispersion of the QTc intervals, when

The larger the QTcD value or the difference QTcD between the maximum value and the minimum value of the QTc interval, the more severe the overall myocardial ischemia of the human body 1 is.

值為17.96，該等QTc間期的最大值與最小值的差距值QTcD為93，而表3的

值為7.58，而該等QTc間期的最大值與最小值的差距值QTcD為41，因此無論是採用該第一種評估模式或該第二評估模式，都能推估出表1的病患整體心肌缺血的嚴重程度都較表3的病患嚴重，而且表1的

值與QTcD都顯示出表1的患者可能需要進行較積極的治療，因此具有一致的評估結果。 For example, taking the analysis results of 16 ECG signals as an example, Table 1

value is 17.96, and the gap value QTcD between the maximum value and minimum value of these QTc intervals is 93, while those in Table 3

is 7.58, and the difference QTcD between the maximum value and the minimum value of these QTc intervals is 41, so whether the first evaluation mode or the second evaluation mode is used, the patients in Table 1 can be estimated The severity of overall myocardial ischemia is more serious than that of the patients in Table 3, and the patients in Table 1

Both values and QTcD show that the patients in Table 1 may need more aggressive treatment, so they have consistent assessment results.

值為13.35，該等QTc間期的最大值與最小值的差距值QTcD為93，而表7的

值為9.11，該等QTc間期的最大值與最小值的差距值QTcD為79，因此同樣能推估出表5的病患（即表1的病患）整體心肌缺血的嚴重程度較表7的病患（即表3的病患）嚴重，也就是說無論以16個心電訊號或是24個心電訊號進行分析都能達到一致的分析結果。 In addition, taking the analysis results of 24 ECG signals as an example, taking Table 5 and Table 7 of the same patient as Table 1 and Table 3 respectively, Table 5

The value is 13.35, and the gap value QTcD between the maximum value and the minimum value of these QTc intervals is 93, while the values in Table 7

value is 9.11, and the gap value QTcD between the maximum value and minimum value of these QTc intervals is 79, so it can also be estimated that the severity of the overall myocardial ischemia in the patients in Table 5 (i.e. the patients in Table 1) is higher than that in Table 1. The patients in 7 (namely the patients in Table 3) are serious, that is to say, whether the analysis is performed with 16 ECG signals or 24 ECG signals, the same analysis results can be achieved.

In addition, the arrangement of the chest electrodes 21 is not limited to the arrangement shown in Fig. 3 and Fig. 10. Taking Fig. 15 as an example, Fig. 15 is another arrangement of 24 chest electrodes 21. For the lateral positions of the chest electrodes 21 corresponding to the human body 1, three chest electrodes 21 in the chest electrodes 21 correspond to the right sternal margin 11, and 5 chest electrodes 21 correspond to the left sternal margin 111, Five chest electrodes 21 correspond to the midline 113 between the left sternal border 111 and the left clavicle midline 112, four chest electrodes 21 correspond to the left clavicle midline 112, and four chest electrodes 21 correspond to the left clavicle midline 112. The anterior underarm line 114 and the three chest electrodes 21 correspond to the left underarm midline 13; in terms of the longitudinal positions of the chest electrodes 21 corresponding to the human body 1, one of the chest electrodes 21 The chest electrodes 21 correspond to the second intercostal space corresponding to the height of the right sternal border 11, the four chest electrodes 21 correspond to the third intercostal space corresponding to the height of the right sternal border 11, and the five chest electrodes 21 correspond to the fourth intercostal space. At the height of the right sternal margin 11, the five chest electrodes 21 correspond to the fifth intercostal space corresponding to the height of the right sternal margin 11, and the 4 chest electrodes 21 correspond to the sixth intercostal space corresponding to the height of the right sternal margin 11, and correspond to The five chest electrodes 21 between the left sternal border 111 and the left clavicle midline 112 on the midline 113 correspond to a third rib, the fourth rib, the fifth rib, and the sixth rib, respectively. And the height of a seventh rib.

After actual measurement and analysis, according to the arrangement of the chest electrodes 21 disclosed in FIG. 15 , when analyzing the location and scope of myocardial ischemia, and the severity of the overall myocardial ischemia of the patient, it can be obtained as shown in FIG. 3 and FIG. 10 . The analysis results of the arrangement of the chest electrodes 21 are consistent.

In addition, referring to FIG. 16 , the number of the chest electrodes 21 can also be 36. In terms of the lateral positions of the chest electrodes 21 corresponding to the human body 1, seven of the chest electrodes 21 The electrodes 21 correspond to the right sternal border 11, the seven front electrodes 21 correspond to the left sternal border 111, and the seven front electrodes 21 correspond to the midlines 113, 6 between the left sternal border 111 and the left clavicle midline 112. One chest electrode 21 corresponds to the left clavicle midline 112, five chest electrodes 21 correspond to the left underarm front edge line 114, and four chest electrodes 21 correspond to the left underarm midline 13; 21 corresponds to the longitudinal position of the human body 1, two of the chest electrodes 21 correspond to the first intercostal space corresponding to the height of the right sternal border 11, and three chest electrodes 21 correspond to the second The intercostal space corresponds to the height of the right sternal border 11, the 4 chest electrodes 21 correspond to the third intercostal space corresponding to the height of the right sternal border 11, the 5 front chest electrodes 21 correspond to the fourth intercostal space corresponding to the height of the right sternal border 11, 5 chest electrodes 21 correspond to the height of the right sternal border 11 in the fifth intercostal space, 5 chest electrodes 21 correspond to the height of the sixth intercostal space corresponding to the height of the right sternal border 11, and 5 chest electrodes 21 correspond to the height of the right sternal border 11. The intercostal space corresponds to the height of the right sternal border 11, and corresponds to the seven front chest electrodes 21 on the midline 113 between the left sternal border 111 and the left clavicle midline 112, corresponding to a second rib and the first rib respectively. The heights of three ribs, the fourth rib, the fifth rib, the sixth rib, the seventh rib and the eighth rib.

After actual measurement and analysis, according to the arrangement of the chest electrodes 21 disclosed in Fig. 16, when analyzing the location and scope of myocardial ischemia, and the severity of the overall myocardial ischemia of the patient, it can also be obtained as shown in Fig. 3 and Fig. 10 and FIG. 15 show that the arrangement of the chest electrodes 21 is consistent with the analysis results.

According to the above description, the advantages of the myocardial ischemia detection device and the myocardial ischemia detection method of the present invention include:

1. The present invention calculates the eigenvalues of the QT intervals and the RR intervals to detect the myocardial ischemia position of the human body 1. Compared with the existing analysis method of changing the waveform of the ST segment, the QT Intervals and the RR intervals are less affected by chest wall impedance, noise, and baseline shift, thus avoiding estimation errors.

2. The present invention uses the ECG signal measurement position corresponding to at least one of the lowest eigenvalues to detect the position of myocardial ischemia. The falling waveform change is used as the evaluation basis, and the detection method of the present invention is relatively easy and can effectively improve its sensitivity.

3. Image the numerical differences and corresponding distribution positions of these characteristic values on the output unit 6 with different color scales, so that the user can easily and conveniently understand the high and low distribution of these characteristic values, so as to facilitate the evaluation of the myocardium The location of ischemia and the extent of myocardial ischemia can effectively shorten the assessment time.

值或該等QTc間期的最大值與最小值的差距值QTcD）評估整體心肌缺血的嚴重程度，十分地簡易。 Fourth, with a single indicator (i.e.

Value or the difference between the maximum value and the minimum value of the QTc interval (QTcD) evaluates the severity of the overall myocardial ischemia, which is very simple.

5. By arranging at least 16 of the chest electrodes 21, the chest electrodes 21 are arranged on the special layout position of the reference surface 100, and the processing unit 3 calculates the heart rate based on the ECG signals. can completely provide the characteristics of the ECG signal of the reference surface 100, so even if it is applied to the human body 1 without urging, the position and range of chronic and acute myocardial ischemia of the human body 1 can be estimated, and because the The number of the chest electrodes 21 is only at least 16, so there is no need to increase too much manufacturing cost and it is very convenient to use.

6. Since the chest electrodes 21 are arranged on the reference surface 100, the characteristics obtained by calculating the ECG signals measured by the 16 chest electrodes 21 can be calculated by two-dimensional interpolation Value, expanded to 24 points of eigenvalues, compared with the traditional 12-lead ECG, it can improve the accuracy of judgment, and compared with the existing method of obtaining ECG with more than one hundred electrodes, it can reduce the chest The number of the front electrodes 21 reduces the cost and simplifies the positioning steps when the electrodes are attached to the human body 1 .

7. By setting the wearing unit 7, when the human body 1 wears the wearing unit 7, the chest electrodes 21 respectively correspond to the predetermined positions of the reference surface 100, so the setting of the chest electrodes 21 can be simplified. The positioning and operation steps of the human body 1 can speed up the operation process and ensure the correctness of the placement of the chest electrodes 21 .

In addition, it should be noted that in this embodiment, each feature value is the QTc interval of the respective ECG signal, however, in other implementations, each feature value can also be the QTc interval of the respective ECG signal The same effect can also be achieved according to the above-mentioned detection steps for the QT interval of the signal (that is, the RR interval is not corrected, so there is no need to capture the RR interval of each ECG signal).

In summary, the myocardial ischemia detection device and the myocardial ischemia detection method of the present invention detect the myocardial ischemia location of the human body 1 by calculating the characteristic values with the QT intervals and the RR intervals, Since the QT intervals and the RR intervals are less affected by chest wall impedance, noise, and baseline offset than the existing analysis methods based on ST-segment waveform changes, evaluation errors can be avoided, so it is true Can reach the purpose of the present invention.

But the above-mentioned ones are only embodiments of the present invention, and should not limit the scope of the present invention. All simple equivalent changes and modifications made according to the patent scope of the present invention and the content of the patent specification are still within the scope of the present invention. Within the scope covered by the patent of the present invention.

1: human body 100: Reference surface 11: Right sternal border 111: Left sternal border 112: Midline of the left clavicle 113: center line 114: Front edge line of left armpit 12: Horizontal line 13: Left axillary midline 14: Horizontal line 2: Measuring unit 21: chest electrodes 22: Signal buffer 23: Signal amplifier 24: filter 25: Signal converter 26: limb conduction electrode 3: Processing unit 4: Database unit 41: Compare information 411: compare area 5: Input unit 6: Output unit 7: Wearing unit

Other features and effects of the present invention will be clearly presented in the implementation manner with reference to the drawings, wherein: Fig. 1 is a system block diagram of an embodiment of the myocardial ischemia detection device of the present invention; Fig. 2 is a schematic diagram illustrating that a reference plane of a human body corresponding to several ECG signals obtained in this embodiment is a horizontal line corresponding to the height of the right sternal border of the human body and a first intercostal space , a left axillary midline, and a horizontal line of the eighth rib corresponding to the height of the right sternal border; Fig. 3 is a schematic diagram illustrating the setting positions of 16 chest electrodes of this embodiment; FIG. 4 is a schematic diagram of a comparison information stored in a database unit of the embodiment; Fig. 5 is a flow chart illustrating the flow process of a method for detecting myocardial ischemia utilizing this embodiment; Fig. 6 is a schematic diagram illustrating that 16 ECG signals were obtained from the left chest of a patient with left recurrent coronary artery (LCX) stenosis, and after two-dimensional interpolation was used to obtain the eigenvalues of 24 points, An image output to an output unit representing the level of the characteristic values of the electrocardiographic signals with different color scales; Fig. 7 is another schematic diagram illustrating that 16 ECG signals were obtained from the left chest of a patient with right coronary artery (RCA) stenosis, and the eigenvalues of 24 points were obtained by two-dimensional interpolation. Representing the level of the characteristic values of the ECG signals with different color levels and outputting the image on the output unit; Fig. 8 is yet another schematic diagram illustrating that 16 ECG signals were obtained from the left chest of a patient with left anterior descending coronary artery (LAD) stenosis, and the eigenvalues of 24 points were obtained by two-dimensional interpolation calculation After that, use different color scales to represent the level of the characteristic values of the ECG signals and output the image on the output unit; Fig. 9 is another schematic diagram illustrating that 16 ECG signals were obtained from the left chest of a patient with three coronary artery stenosis (3VD), and the eigenvalues of 24 points were obtained by two-dimensional interpolation calculation , using different color scales to represent the level of the characteristic values of the ECG signals and output the image on the output unit; Fig. 10 is a schematic diagram similar to Fig. 3, illustrating a change in the arrangement of the number of electrodes in front of the chest of this embodiment to 24; Fig. 11 is a diagram similar to Fig. 6, illustrating that 24 ECG signals were obtained from the left chest of a patient with left recurrent coronary artery (LCX) stenosis, and 36 points were obtained by two-dimensional interpolation calculation After the eigenvalues, the images output on the output unit are represented by different color levels of the eigenvalues of the ECG signals; Fig. 12 is a diagram similar to Fig. 7, illustrating that 24 ECG signals were obtained from the left chest of the patient with right coronary artery (RCA) stenosis, and the characteristics of 36 points were obtained by two-dimensional interpolation calculation After the value, use different color scales to represent the level of the characteristic values of the ECG signals and output the image on the output unit; Fig. 13 is a diagram similar to Fig. 8, illustrating that 24 ECG signals were obtained from the left chest of a patient with left anterior descending coronary artery (LAD) stenosis, and 36 points were obtained by two-dimensional interpolation calculation After the eigenvalues, the images output on the output unit are represented by different color levels of the eigenvalues of the ECG signals; Fig. 14 is a diagram similar to Fig. 9, illustrating that 24 ECG signals were obtained from the left chest of the patient with three coronary artery stenosis (3VD), and the characteristics of 36 points were obtained by two-dimensional interpolation calculation After the value, use different color scales to represent the level of the characteristic values of the ECG signals and output the image on the output unit; Fig. 15 is another schematic diagram similar to Fig. 3, illustrating another variation setting mode in which the number of electrodes in front of the chest of this embodiment is changed to 24; and Fig. 16 is yet another schematic diagram similar to Fig. 3, illustrating a variation arrangement in which the number of chest electrodes in this embodiment is changed to 36.

2: Measuring unit

21: chest electrodes

22: Signal buffer

23: Signal amplifier

24: filter

25: Signal converter

26: limb conduction electrode

3: Processing unit

4: Database unit

5: Input unit

6: Output unit

Claims (14)

A myocardial ischemia detection device, suitable for a human body, the myocardial ischemia detection device includes: A measurement unit, including four limb conducting electrodes, and several chest electrodes, the limb conducting electrodes and the chest electrodes are suitable for obtaining several ECG signals of the human body, at least some of the chest electrodes The measurement position of corresponds to the left chest of the human body; and A processing unit, the signal is connected to the measurement unit and can receive the ECG signals, the processing unit can extract the QT intervals of the ECG signals, and use the QT intervals to calculate a number corresponding to the ECG signals respectively The characteristic values of several points on the left chest of the human body are measured according to the ECG signal corresponding to at least one of the lowest characteristic values, so as to detect the myocardial ischemia position of the human body. The myocardial ischemia detection device as described in Claim 1, further includes a database unit, the database unit stores a comparison information, and the processing unit can compare with the comparison information according to the distribution state of the characteristic values Yes, to detect the extent of myocardial ischemia. The myocardial ischemia detection device according to claim 2, wherein the chest electrodes of the measurement unit and the chest electrodes are adapted to obtain at least 16 of the electrocardiographic signals of a reference surface of the human body, The reference plane is defined by a right sternal margin of the human body, a horizontal line corresponding to the height of the right sternal margin of the first intercostal space, a left axillary midline, and a horizontal line corresponding to the height of the right sternal margin of the eighth rib out. The myocardial ischemia detection device as described in Claim 2, wherein the processing unit can also extract the RR intervals of the ECG signals, and the processing unit calculates the QT intervals and the RR intervals The QTc intervals at these points are respectively used as the characteristic values. The myocardial ischemia detection device according to Claim 4 further includes an output unit, and the processing unit can image the numerical differences and corresponding distribution positions of the feature values on the output unit in different color scales. The myocardial ischemia detection device according to claim 4, wherein the processing unit can also calculate a discrete parameter with an evaluation parameter algorithm, and evaluate the severity of the overall myocardial ischemia of the human body according to the discrete parameter, the evaluation The parameter algorithm is:

,in

is the discrete parameter, S is the total number of such points,

is the QTc interval of a specific point, n is the number of points closest to the specific point corresponding to the position of the human body,

is the QTc interval of one of the points closest to the point corresponding to the position of the human body. The myocardial ischemia detection device according to claim 4, wherein the processing unit can also calculate the difference QTcD between the maximum value and the minimum value of the QTc intervals in the points, and based on the QTc intervals The difference between the maximum value and the minimum value evaluates the severity of the overall myocardial ischemia in the human body. A method for detecting myocardial ischemia, comprising: a measuring step, obtaining several electrocardiographic signals of a human body, at least part of which are measured at positions corresponding to the left chest of the human body; A feature extraction step, using a processing unit to extract the QT interval of each ECG signal, and calculating several feature values corresponding to several points of the left chest of the human body according to the QT interval; and A first analysis step, comparing the point corresponding to at least one of the characteristic values with the position corresponding to the left chest of the human body, so as to detect the myocardial ischemia position. The method for detecting myocardial ischemia according to Claim 8, wherein the first analysis step further includes comparing the distribution of the characteristic values with a comparison information to detect the extent of myocardial ischemia. The myocardial ischemia detection method as described in Claim 9, wherein the measuring step is to obtain the ECG signals of a reference surface of the human body, the reference surface is composed of a right sternal margin of the human body, a first The intercostals are defined by a horizontal line corresponding to the height of the right sternal border, a left axillary midline, and a horizontal line of the eighth rib corresponding to the height of the right sternal border. The myocardial ischemia detection method as described in Claim 9, wherein the feature extraction step also extracts the RR intervals of the ECG signals, and calculates the QT intervals and the RR intervals The QTc intervals of the points are respectively used as the characteristic values. The method for detecting myocardial ischemia according to claim 11, wherein the first analysis step is to compare the feature values according to the position corresponding to the left chest of the human body and represent the level of the feature values with different color levels An image is generated, and the extent of myocardial ischemia is detected by comparing the image with the comparison information. According to the myocardial ischemia detection method described in claim 11, the feature values calculated in the feature extraction step are based on the ECG signals to calculate the QTc interval corresponding to the corresponding point, and the myocardial ischemia detection method also A second analysis step is included. The second analysis step is to calculate a discrete parameter by an evaluation parameter algorithm, and evaluate the severity of the overall myocardial ischemia of the human body according to the discrete parameter. The evaluation parameter algorithm is:

,in

is the discrete parameter, S is the total number of such points,

is the QTc interval of a specific point, n is the number of points closest to the point corresponding to the position of the human body,

is the QTc interval of one of the points closest to this point corresponding to the position of the human body. The myocardial ischemia detection method as described in claim 11, wherein the feature values calculated in the feature extraction step are the QTc intervals corresponding to the points calculated based on the ECG signals, and the myocardial ischemia detection method The method also includes a second analysis step, the second analysis step is to calculate the difference between the maximum value and the minimum value of the QTc interval at the points, and according to the difference between the maximum value and the minimum value of the QTc interval The gap value QTcD assesses the severity of global myocardial ischemia in the subject.

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