JP5361644B2 - ECG data processing apparatus, ECG data processing method, and ECG data processing program - Google Patents

Description

  The present invention relates to an electrocardiogram data processing apparatus, an electrocardiogram data processing method, and an electrocardiogram data processing program.

  The ECG waveform includes components such as a P wave, a QRS wave, a T wave, and a U wave. Among these, the U wave is a component generated following the T wave, and generally the amplitude thereof takes a positive value. A U wave having a negative amplitude is classified as a negative U wave or a biphasic U wave depending on its shape.

  In the following description, the biphasic U wave is a kind of negative U wave unless otherwise specified.

  Negative U waves that may appear mainly in chest induction are abnormal electrocardiograms observed in cases of ischemic heart disease, idiopathic cardiomyopathy, cardiac hypertrophy, etc. (see, for example, Non-patent Document 1). Significant significance.

  Furthermore, it is known that negative U waves have a high appearance rate in the electrocardiogram before the onset of acute myocardial infarction, and are an important finding suggesting the possibility of predicting infarction.

  Therefore, although it is required to recognize the shape of the U wave with high accuracy, the U wave often has a very small amplitude compared to other components. Moreover, although it is generally considered that the U wave represents a part of the repolarization of the ventricular muscle, the definition is ambiguous. For this reason, in the electrocardiogram, not only the shape of the U wave but also the presence of the U wave itself may not be easily visible.

"Disease can be seen vol.2 Cardiovascular system 2nd edition", edited by National Institute of Medical Information Science, March 2008, p. 38 P. W. Macfarlane et al., “12-lead vector electrocardiogram”, published by Medical Electro Times, Inc., June 1996, p. 33-36

  However, conventionally, no proposal has been made for automatic detection of U-waves with high accuracy by various devices that handle ECG data.

  An object of the present invention is to provide an electrocardiogram data processing apparatus, an electrocardiogram data processing method, and an electrocardiogram data processing program capable of automatically detecting a U wave of an electrocardiogram with high accuracy.

  An electrocardiogram data processing apparatus of the present invention is an electrocardiogram data processing apparatus for detecting a U wave in a measured electrocardiogram that is a scalar electrocardiogram measured using electrodes, and converts first electrocardiogram data indicating the measured electrocardiogram. To generate second electrocardiogram data indicating a vector electrocardiogram-scalar electrocardiogram, and second electrocardiogram data generated from the feature points of the U loop in the vector electrocardiogram composed of the vector electrocardiogram-scalar electrocardiogram A U-loop feature point detection unit that detects a point on the waveform of the measurement electrocardiogram corresponding to the detected feature point of the U-loop as a division point of the U-wave in the measurement electrocardiogram A segment point detection unit.

  The electrocardiogram data processing method of the present invention is an electrocardiogram data processing method for detecting a U wave in a measured electrocardiogram which is a scalar electrocardiogram measured using electrodes, and converts first electrocardiogram data indicating the measured electrocardiogram. To generate second electrocardiogram data indicating a vector electrocardiogram-scalar electrocardiogram, and second electrocardiogram data generated from the feature points of the U loop in the vector electrocardiogram constituted by the vector electrocardiogram-scalar electrocardiogram U-loop feature point detection step for detecting based on the U-wave, and a point on the waveform of the measured electrocardiogram corresponding to the detected feature point of the U-loop as a U-wave division point in the measured electrocardiogram A dividing point detecting step.

  The electrocardiogram data processing program of the present invention converts the first electrocardiogram data indicating the measured electrocardiogram into a computer in an electrocardiogram data processing apparatus that detects a U wave in a measured electrocardiogram that is a scalar electrocardiogram measured using electrodes. To generate second electrocardiogram data indicating a vector electrocardiogram-scalar electrocardiogram, and second electrocardiogram data generated from the feature points of the U loop in the vector electrocardiogram composed of the vector electrocardiogram-scalar electrocardiogram U-loop feature point detection function for detecting based on the U-wave and a point on the waveform of the measurement electrocardiogram corresponding to the detected feature point of the U-loop as a U-wave division point in the measurement electrocardiogram A division point detection function is realized.

  According to the present invention, the U wave of an electrocardiogram can be automatically detected with high accuracy.

The block diagram which shows the structure of the electrocardiogram data processing system of one embodiment of this invention The flowchart which shows operation | movement of the electrocardiogram data processing system of one embodiment of this invention Diagram for explaining standard 12-lead ECG The flowchart which shows the operation | movement of the U wave automatic detection of one embodiment of this invention The figure for demonstrating the electrocardiogram conversion process performed in the U wave automatic detection of one embodiment of this invention The figure for demonstrating the process leading to U wave division point detection in the U wave automatic detection of one embodiment of this invention The figure which shows the 1st example of the result output of the U wave automatic detection of one embodiment of this invention The figure which shows the 2nd example of the result output of the U wave automatic detection of one embodiment of this invention The figure which shows the 3rd example of the result output of the U wave automatic detection of one embodiment of this invention The figure for demonstrating the operation | movement of the U wave analysis of one embodiment of this invention

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a block diagram showing a configuration of an electrocardiogram data processing system including an electrocardiogram data processing apparatus according to an embodiment of the present invention.

  1, the electrocardiogram data processing system mainly includes an electrocardiogram data processing apparatus 100, a display 120, a printer 130, an electrocardiograph 140, and an input device 160.

  The electrocardiogram data processing apparatus 100 includes a calculation unit 101, a display interface (hereinafter abbreviated as “I / F”) 102, a printer I / F 103, an electrocardiograph I / F 104, a storage unit 105, and an input device I / F 106.

  The arithmetic unit 101 includes an arithmetic processing device and a storage device that stores an electrocardiogram data processing program. The arithmetic unit 101 executes an electrocardiogram data processing program in the arithmetic processing unit to realize an electrocardiogram conversion function, a U-loop feature point detection function, and a U-wave segment point detection function in U-wave automatic detection described later. Realizes parameter measurement function and shape determination function in wave analysis. Therefore, the calculation unit 101 constitutes an electrocardiogram conversion unit, a U loop feature point detection unit, a U wave segment point detection unit, a parameter measurement unit, and a shape determination unit.

  In addition, the calculation unit 101 performs execution start, execution stop and execution condition (threshold value, etc.) setting of the electrocardiogram data processing program, control of various measuring devices such as the electrocardiograph 140, and control of various peripheral devices such as the display 120 and the printer 130. , According to the input command.

  The display I / F 102 is an I / F that connects the display 120 such as an LCD (Liquid Crystal Display) or a CRT (Cathode Ray Tube) display device and the electrocardiogram data processing device 100 so that they can communicate with each other. Data exchanged with the device 100 passes through the display I / F 102.

  The printer I / F 103 is an I / F that connects the laser-type or thermal-head printer 130 and the electrocardiogram data processing apparatus 100 so that they can communicate with each other, and is exchanged between the printer 130 and the electrocardiogram data processing apparatus 100. The data passes through the printer I / F 103.

  The electrocardiograph I / F 104 uses a limb electrode unit 141 and a chest electrode unit 142 to generate a standard 12-lead electrocardiogram (hereinafter simply referred to as a “12-lead electrocardiogram”) from a subject (that is, a subject for electrocardiogram measurement). This is an I / F that connects the electrocardiograph 140 to be measured and the electrocardiogram data processing apparatus 100 so that they can communicate with each other. The data exchanged between the electrocardiograph 140 and the electrocardiogram data processing apparatus 100 is an electrocardiograph I / F. Via F104.

  The storage unit 105 includes a storage device such as a hard disk drive or a semiconductor storage device. The storage unit 105 records the data received from the electrocardiograph 140 and the data obtained as a result of the U-wave automatic detection operation and the U-wave analysis operation by the calculation unit 101 in an internal storage device.

  The input device I / F 106 is an I / F that connects the input device 160 such as a mouse or a keyboard and the electrocardiogram data processing device 100 in a communicable manner. An input signal generated when a medical staff such as a doctor operates using the input device 160 is transmitted to the calculation unit 101 via the input device I / F 106 and is interpreted as an input command by the calculation unit 101.

  The configuration of the electrocardiogram data processing system according to this embodiment has been described above. The above configuration can be implemented with various modifications.

  For example, in the present embodiment, the electrocardiogram data processing apparatus 100 has a configuration independent of the electrocardiograph 140, but the electrocardiogram data processing apparatus 100 may be provided inside the electrocardiograph 140. The electrocardiogram data processing apparatus 100 can also be mounted on a stress test system for performing a stress test using a treadmill or the like. That is, the present invention can be applied to various biological information measuring devices that handle electrocardiogram data such as an electrocardiograph and a stress test system.

  In this embodiment, an electrocardiograph 140 that measures a 12-lead electrocardiogram is used. However, any electrocardiograph that measures a scalar electrocardiogram, such as a Holter electrocardiograph that mainly measures a 1ch or 2ch electrocardiogram, is used. An electrocardiograph can be used.

  Next, an operation in the electrocardiogram data processing system having the above configuration will be described.

  FIG. 2 is a flowchart showing operations executed in the electrocardiogram data processing system.

  First, in step S100, the electrocardiograph 140 measures a 12-lead electrocardiogram from the subject using the extremity electrode unit 141 and the chest electrode unit 142. The electrocardiograph 140 acquires a 12-lead electrocardiogram as an electrical signal, and performs analog-digital conversion on the 12-lead electrocardiogram to generate 12-lead ECG data that is digital data indicating the 12-lead ECG. The electrocardiogram data is recorded in a storage device inside the electrocardiograph 140 and transmitted to the electrocardiogram data processing device 100.

  A 12-lead electrocardiogram 170 shown in FIG. 3 is an example of a 12-lead electrocardiogram measured in step S100. The 12-lead electrocardiogram consists of the standard limb leads I, II and III, the monopolar limb leads aVR, aVL and aVF, and the chest leads V1, V2, V3, V4. Induction, V5 induction and V6 induction. In this induction method, a potential difference between electrodes worn on the body surface of a subject or a difference between a potential at the worn electrode and a reference potential is measured. That is, the 12-lead electrocardiogram measured using electrodes in the present embodiment is a kind of scalar electrocardiogram that expresses a temporal change in the magnitude of the electromotive force by a waveform on the time axis.

  When the 12-lead electrocardiogram is measured, the electrocardiogram data processing apparatus 100 automatically detects the U wave (step S200), analyzes the U wave (step S300), and outputs the analysis result (step S400).

  FIG. 4 is a flowchart showing the U-wave automatic detection operation executed in step S200 in the electrocardiogram data processing apparatus 100.

  First, in step S210, the operation unit 101 receives the 12-lead electrocardiogram data transmitted from the electrocardiograph 140 via the electrocardiograph I / F 104, thereby acquiring the 12-lead ECG data as the first electrocardiogram data.

  Thereby, automatic detection of a U wave can be performed in real time about the measured 12-lead ECG.

  In addition, the calculation unit 101 causes the storage unit 105 to store the received 12-lead ECG data.

  Note that the calculation unit 101 can also acquire 12-lead ECG data by reading 12-lead ECG data received from the electrocardiograph 140 in the past from the storage unit 105.

  In addition, the calculation unit 101 may cause the display 120 or the printer 130 to output the 12-lead electrocardiogram indicated in the acquired 12-lead ECG data in step S400.

  In step S220, the calculation unit 101 generates XYZ lead electrocardiogram data as second electrocardiogram data by converting the acquired 12-lead ECG data using, for example, an inverse Dower Matrix (see, for example, Non-Patent Document 2). .

  More specifically, as shown in FIG. 5, the calculation unit 101 extracts data of a portion corresponding to a partial electrocardiogram 171 including a specific or arbitrary one-beat waveform from the acquired 12-lead electrocardiogram data. Then, the extracted data is converted into XYZ lead electrocardiogram data which is digital data indicating the XYZ lead electrocardiogram 172.

  Here, the XYZ lead electrocardiogram includes X lead, Y lead and Z lead. Since all of these leads express temporal changes in the magnitude of the electromotive force with a waveform on the time axis, the XYZ lead electrocardiogram is a scalar electrocardiogram like the 12 lead electrocardiogram. However, a vector electrocardiogram, particularly a three-dimensional vector electrocardiogram, can be constructed from the X lead, the Y lead, and the Z lead. Therefore, the XYZ lead electrocardiogram is referred to as a vector electrocardiogram configuration scalar electrocardiogram. The three-dimensional vector electrocardiogram expresses temporal changes in the magnitude and direction of electromotive force by a vector loop on a three-dimensional orthogonal coordinate system. Therefore, the waveform of the X lead represents a temporal change in the X coordinate value of the point on the vector loop. Similarly, the Y lead waveform represents a temporal change in the Y coordinate value of a point on the vector loop, and the Z lead waveform represents a temporal change in the Z coordinate value of the point on the vector loop.

  Note that the scalar electrocardiogram shown in the second electrocardiogram data generated in step S220 may constitute a two-dimensional vector electrocardiogram instead of a three-dimensional one. However, in order to automatically detect the U wave with higher accuracy, it is desirable that the vector electrocardiogram-scalar electrocardiogram can constitute a three-dimensional vector electrocardiogram. The scalar electrocardiogram shown in the second electrocardiogram data may be different from the XYZ lead electrocardiogram as long as it can constitute a three-dimensional vector electrocardiogram.

  When the first electrocardiogram data acquired in step S210 is not 12-lead ECG data (for example, data indicating a Holter electrocardiogram), the calculation unit 101 calculates from the acquired first ECG data. The 12-lead ECG data can be synthesized and the synthesized 12-lead ECG data can be converted into XYZ lead ECG data.

  Further, the calculation unit 101 may cause the display 120 or the printer 130 to output the XYX lead electrocardiogram shown in the generated XYZ lead electrocardiogram data in step S400.

  In step S230, the calculation unit 101 creates a three-dimensional vector electrocardiogram by plotting the XYZ lead electrocardiogram shown in the generated XYZ lead electrocardiogram data in a three-dimensional orthogonal coordinate system.

  Here, as shown in FIG. 6, among the XYZ lead electrocardiogram data showing the XYZ lead electrocardiogram 172, the data of the part corresponding to the waveform part that is located behind the QRS wave and can include the T wave and the U wave in the 12 lead electrocardiogram. By extracting and using, a three-dimensional vector electrocardiogram having a vector loop 173 including a T loop 173T and a U loop 173U is created.

  Note that the calculation unit 101 may create a three-dimensional vector electrocardiogram having a vector loop corresponding to the entire one beat.

  In addition, the calculation unit 101 may cause the display 120 or the printer 130 to output the three-dimensional vector electrocardiogram created in this way in step S400.

  In step S240, the calculation unit 101 calculates the distance from the origin O of the three-dimensional orthogonal coordinate system for each point on the vector loop 173. For this distance calculation, the XYZ lead electrocardiogram data generated in step S220 can be used.

  In particular, among the XYZ lead electrocardiogram data, the data of the portion corresponding to the waveform portion that is located behind the QRS wave and can include the T wave and the U wave in the 12 lead electrocardiogram is extracted and used. Thereby, the amount of calculation can be reduced.

As described above, in the XYZ lead electrocardiogram, the X lead, the Y lead, and the Z lead respectively represent the X coordinate value, the Y coordinate value, and the Z coordinate value of the point on the vector loop. Therefore, if the amplitudes of the X lead, Y lead, and Z lead at time t are x _t , y _t , and z _t , the distance from the origin O (x ₀ , y ₀ , z ₀ ) at this point is ,
Can be calculated. Note that (x ₀ , y ₀ , z ₀ ) = (0, ₀ , ₀ ).

  Thereby, the calculation unit 101 can know the temporal change in the distance between the point on the vector loop 173 and the origin O. As shown in FIG. 6, a waveform 174 indicating a temporal change in the calculated distance includes a waveform portion 174T indicating a temporal change in the distance between a point on the T loop 173T and the origin O, and a point on the U loop 173U. And a waveform portion 174U indicating a temporal change in the distance from the origin O. Therefore, the first point having a smaller amplitude than both the front and rear points on the waveform 174 can be defined as a point BUL corresponding to the start point of the U loop 173U. Further, the point where the amplitude is larger than both the front and rear points on the waveform 174 can be defined as a point TUL corresponding to the apex of the U loop 173U. In addition, a second point having a smaller amplitude than both the front and rear points on the waveform 174 can be defined as a point EUL corresponding to the end point of the U loop 173U.

  In step S250, the calculation unit 101 calculates the minimum value and the maximum value of the distance calculated in step S240, and calculates a point on the vector loop 173 where the distance from the origin O is the minimum value and the maximum value as U It is detected as a feature point of the loop 173U. The calculation of the minimum value and the maximum value can be performed by a method such as differentiation of the distance calculated in step S240.

  In the present embodiment, the feature points to be detected include the start point, vertex and end point of the U loop 173U. That is, the calculation unit 101 detects the first point at which the distance from the origin O is a minimum value as the start point of the U loop 173U, and determines the point at which the distance from the origin O is a maximum value of the U loop 173U. A second point that is detected as a vertex and has a minimum value from the origin O is detected as an end point of the U loop 173U.

  Thus, in the present embodiment, the start point, vertex, and end point of the U loop 173U are derived from the distance between the point on the vector loop 173 and the origin O. The distance is obtained from the sum of the square of the non-negative X coordinate value, the square of the Y coordinate value, and the square of the Z coordinate value. Therefore, the start point, vertex, and end point of the U loop 173U can be detected with high accuracy.

  The feature point to be detected may be at least one of the start point, vertex, and end point of the U loop 173U, or may be a point that is different from any of the start point, vertex, and end point of the U loop 173U.

  In addition, the calculation unit 101 may cause the display 120 or the printer 130 to output the distance calculation result in step S240 and the U-loop feature point detection result in step S250 in step S400.

  In step S260, operation unit 101 detects a U-wave division point in partial electrocardiogram 171 indicated in the data extracted from the 12-lead electrocardiogram data in step S220, particularly in chest lead electrocardiogram 175.

  This U-wave division point detection is performed based on the U-loop feature point detection result in step S250.

  More specifically, a point on the waveform of the chest lead electrocardiogram 175 located at the same time as the detected start point of the U loop 173U is detected as the start point BUW of the U wave. Further, a point on the waveform of the chest lead electrocardiogram 175 located at the same time as the detected vertex of the U loop 173U is detected as the vertex TUW of the U wave. A point on the waveform of the chest lead electrocardiogram 175 located at the same time as the end point of the detected U loop 173U is detected as the end point EUW of the U wave.

  As a result, the waveform portion from the start point BUW to the end point EUW in the chest lead electrocardiogram 175 can be recognized as the U wave 175U.

  The method of deriving the start point BUW, the vertex TUW, and the end point EUW of the U wave 175U is not limited to the above-described method, and other methods are possible. For example, both the start point BUW and the end point EUW of the U wave 175U may be derived from only one of the start point and the end point of the U loop 173U.

  However, as in the present embodiment, the start point BUW of the U wave 175U is derived with reference to the start point of the U loop 173U, the vertex TUW of the U wave 175U is derived with reference to the vertex of the U loop 173U, and the end point EUW of the U wave 175U Deriving from the end point of the U loop 173U as a reference is desirable in terms of U-wave segment point detection accuracy. This is because in the present embodiment, as described above, the start point, vertex, and end point of the U loop 173U can be detected with high accuracy.

  Further, U-wave segment point detection may be performed not only on the chest lead electrocardiogram 175 but also on the standard limb lead electrocardiogram and the monopolar limb lead electrocardiogram. However, since the abnormality of the U wave, that is, the negative U wave appears mainly in the chest lead, even if the U wave segment point detection is performed on the chest lead electrocardiogram 175 as in the present embodiment, the negative U wave is not detected. It can be detected with high accuracy.

  In addition, the calculation unit 101 may cause the display 120 or the printer 130 to output the U wave division point detection result in step S400.

  The operation of U wave automatic detection has been described above.

  The U wave automatic detection can automatically detect the U wave with high accuracy, and when the result is output to the display 120 or the printer 130, the U wave can be easily visually recognized.

  For example, FIG. 7 shows the output of the U-wave automatic detection result for the sample electrocardiogram of the left ventricular hypertrophy patient. In this figure, a plurality of beats of the chest lead electrocardiogram 170a, a waveform 174a indicating the distance between a point on the vector loop obtained based on the data indicating the chest lead electrocardiogram 170a and the origin of the three-dimensional orthogonal coordinate system, Also shown is a chest lead electrocardiogram 175a for one beat of the chest lead electrocardiogram 170a. Further, the line B connecting the start point of the detected U wave 175aU and the vertex of the detected U wave 175aU are aligned with the points on the waveform 174a corresponding to the start point, vertex and end point of the detected U loop. A connecting line T and a line E connecting the end points of the detected U wave 175aU are shown. For this reason, the U wave can be recognized at a glance in this sample electrocardiogram.

  Further, FIG. 8 shows the output of the U wave automatic detection result for the sample electrocardiogram of the person with myocardial infarction. In this figure, a waveform 174b indicating a distance between a point on a vector loop obtained based on data indicating the measured multiple beats of the chest lead electrocardiogram 170b, the chest lead electrocardiogram 170b, and the origin of the three-dimensional orthogonal coordinate system, Also shown is a chest lead electrocardiogram 175b for one beat of the chest lead electrocardiogram 170b. Further, the line B connecting the start point of the detected U wave 175bU and the apex of the detected U wave 175bU are aligned with the points on the waveform 174b corresponding to the start point, vertex and end point of the detected U loop. A connecting line T and a line E connecting the end points of the detected U wave 175bU are shown. For this reason, the U wave can be recognized at a glance in this sample electrocardiogram.

  Further, FIG. 9 shows the output of the U-wave automatic detection result for the healthy person's sample electrocardiogram. In this figure, a plurality of beats of the chest lead electrocardiogram 170c, a waveform 174c indicating the distance between a point on the vector loop obtained based on the data indicating the chest lead electrocardiogram 170c and the origin of the three-dimensional orthogonal coordinate system, Also shown is a chest lead electrocardiogram 175c for one beat of the chest lead electrocardiogram 170c. Further, the line B connecting the start point of the detected U wave 175cU and the vertex of the detected U wave 175cU are aligned with the points on the waveform 174c corresponding to the start point, vertex and end point of the detected U loop. A connecting line T and a line E connecting the end points of the detected U wave 175cU are shown. For this reason, the U wave can be recognized at a glance in this sample electrocardiogram.

  In the conventional method, since the U wave has to be identified by looking at the waveform of each induction individually, it is difficult to recognize the U wave objectively and accurately. Therefore, the medical staff can easily and quickly visually recognize the U wave, thereby contributing to a dramatic improvement in diagnostic efficiency.

  FIG. 10 is a diagram for explaining the U-wave analysis operation executed in step S300 in the electrocardiogram data processing apparatus 100. FIG. In the description of FIG. 10, a negative U wave and a biphasic U wave are described separately.

  The calculation unit 101 measures parameters including amplitude and duration for the U wave 175U detected in the chest lead electrocardiogram 175. The amplitude is the width of the divergence from the baseline to the waveform within the detected U wave 175U section. The duration is the length of time that the waveform deviates from the baseline within the detected U-wave 175U section.

  Here, when a negative U wave or a biphasic U wave appears only in one of the six chest leads, it is also recognized as an electrocardiogram abnormality. Therefore, for each lead, information AV1, AV2, AV3, AV4, AV5 indicating the amplitude. , AV6 and duration information DV1, DV2, DV3, DV4, DV5, DV6 are desirably obtained.

  And the calculating part 101 determines the shape of U wave 175U by comparing the measured amplitude and duration with a predetermined threshold value. By this shape determination, the calculation unit 101 classifies the U wave 175U into “positive U wave”, “negative U wave”, “biphasic U wave”, and “no U wave”.

  Specifically, in a certain electrocardiogram, when the amplitude in the section of the U wave 175U becomes a positive value that is equal to or greater than the threshold value and does not become a negative value that is equal to or greater than the threshold value, the U wave 175U in the induced electrocardiogram. Is determined to be a “positive U wave”.

  In addition, in a certain electrocardiogram, when the amplitude in the section of the U wave 175U does not become a positive value equal to or greater than the threshold value and becomes a negative value equal to or greater than the threshold value, the U wave 175U in the lead electrocardiogram is “ It is determined to be “negative U wave”.

  In addition, in a certain electrocardiogram, when the amplitude in the section of the U wave 175U becomes a positive value that is equal to or greater than the threshold value and is also a negative value that is equal to or greater than the threshold value, the U wave 175U in the lead electrocardiogram is “two It is determined to be “compatible U-wave”. The biphasic U-wave is further classified into “+ -type” and “− +-type” depending on its shape.

  In addition, in a certain electrocardiogram, when the amplitude in the section of the U wave 175U does not become a positive value equal to or higher than the threshold value or a negative value equal to or higher than the threshold value, the U wave 175U in the lead electrocardiogram It is determined that “None”.

  In the example shown in FIG. 10, the U wave 175U in the V1 lead electrocardiogram and the V2 lead electrocardiogram is determined as a “positive U wave”, and the U wave 175U in the V3 lead electrocardiogram is determined as a “biphasic U wave”. The U wave 175U in the electrocardiogram and the V5 lead electrocardiogram is determined as “negative U wave”, and the U wave 175U in the V6 lead electrocardiogram is determined as “no U wave”.

  By the U wave analysis, it is possible to objectively discriminate the U wave shape that is difficult to discriminate with the human eye, and to automatically detect negative U waves and biphasic U waves that are abnormal electrocardiograms.

  Thus, according to the present embodiment, it is possible to automatically detect a U wave with high accuracy and further to automatically detect a negative U wave with high accuracy. Therefore, there are various examples of application of the negative U-wave automatic detection algorithm based on the present embodiment, such as U-wave inversion monitoring in a stress test and sudden death prediction index calculation.

  The embodiment of the present invention has been described above. The above description is an illustration of a preferred embodiment of the present invention, and the scope of the present invention is not limited to this. That is, the configuration and operation of the apparatus described in the above embodiment are examples, and it is obvious that these can be partially changed, added, and deleted within the scope of the present invention.

  In addition, in order to confirm the usefulness of the negative U-wave automatic detection algorithm based on the above embodiment, when this algorithm was applied to 22,514 adult ECG samples, 255 cases corresponding to 1.13% were negative. U wave was automatically detected. When the negative U wave was visually confirmed for the electrocardiogram detected automatically, it was found that 206 of 255 cases correctly detected the negative U wave. That is, since the accuracy was as high as 80.8%, the usefulness of this negative U wave automatic detection algorithm was confirmed.

100 ECG data processing device 101 arithmetic unit 102 display I / F
103 Printer I / F
104 ECG I / F
105 Storage Unit 106 Input Device I / F
DESCRIPTION OF SYMBOLS 120 Display 130 Printer 140 Electrocardiograph 141 Electrode part for extremities 142 Electrode part for chest 160 Input device

Claims (14)

An electrocardiogram data processing apparatus for detecting a U wave in a measurement electrocardiogram that is a scalar electrocardiogram measured using electrodes,
An electrocardiogram conversion unit for generating second electrocardiogram data indicating a vector electrocardiogram configuration scalar electrocardiogram by converting the first electrocardiogram data indicating the measured electrocardiogram;
A U-loop feature point detector for detecting a feature point of the U-loop in the vector electrocardiogram constituted by the vector electrocardiogram-constituting scalar electrocardiogram based on the generated second electrocardiogram data;
A U-wave segment point detector for detecting a point on the waveform of the measurement electrocardiogram corresponding to the detected feature point of the U loop as a segment point of the U-wave in the measurement electrocardiogram;
An electrocardiogram data processing apparatus. The feature point of the U loop includes at least one of a start point, an end point, and a vertex of the U loop.
The electrocardiogram data processing apparatus according to claim 1. The U-loop feature point detection unit calculates a distance from the origin of the orthogonal coordinate system of the vector electrocardiogram based on the generated second electrocardiogram data for a point on the vector loop of the vector electrocardiogram, and calculates the distance Detecting a feature point of the U-loop based on the result of
The electrocardiogram data processing apparatus according to claim 1. The feature point of the U loop includes at least a start point of the U loop,
The U-loop feature point detection unit detects one of the points on the vector loop of the vector electrocardiogram at which the calculated distance is a minimum point, as the start point of the U-loop;
The electrocardiogram data processing apparatus according to claim 3. The feature point of the U loop includes at least an end point of the U loop,
The U-loop feature point detection unit detects one of the points on the vector loop of the vector electrocardiogram at which the calculated distance is a minimum point as an end point of the U-loop.
The electrocardiogram data processing apparatus according to claim 3. The feature point of the U loop includes at least a vertex of the U loop,
The U-loop feature point detection unit detects one of the points on the vector loop of the vector electrocardiogram at which the calculated distance becomes a maximum point as a vertex of the U-loop;
The electrocardiogram data processing apparatus according to claim 3. The vector electrocardiogram is a three-dimensional vector electrocardiogram;
The U-loop feature point detector calculates a distance from an origin of an orthogonal coordinate system of the three-dimensional vector electrocardiogram for a point on a vector loop of the three-dimensional vector electrocardiogram;
The electrocardiogram data processing apparatus according to claim 3. The division point of the U wave includes at least one of a start point, an end point, and a vertex of the U wave.
The electrocardiogram data processing apparatus according to claim 1. The U-wave segment point detection unit detects a point on the waveform of the measurement electrocardiogram located at the same time as the start point of the U loop detected as a feature point of the U loop as a start point of the U wave.
The electrocardiogram data processing apparatus according to claim 8. The U wave segment point detection unit detects a point on the waveform of the measurement electrocardiogram located at the same time as the end point of the U loop detected as a feature point of the U loop as an end point of the U wave.
The electrocardiogram data processing apparatus according to claim 8. The U-wave segment point detection unit detects a point on the waveform of the measurement electrocardiogram located at the same time as a vertex of the U loop detected as a feature point of the U loop as a vertex of the U wave.
The electrocardiogram data processing apparatus according to claim 8. A parameter measuring unit for measuring a parameter for the U wave specified based on the detected division point of the U wave;
A shape determination unit for determining the shape of the U wave based on the measured parameter of the U wave;
The electrocardiogram data processing apparatus according to claim 1, further comprising: An electrocardiogram data processing method for detecting a U wave in a measurement electrocardiogram that is a scalar electrocardiogram measured using electrodes,
An electrocardiogram conversion step of generating second electrocardiogram data indicating a vector electrocardiogram configuration scalar electrocardiogram by converting the first electrocardiogram data indicating the measured electrocardiogram;
A U-loop feature point detection step of detecting a feature point of the U-loop in the vector electrocardiogram constituted by the vector electrocardiogram-constituting scalar electrocardiogram based on the generated second electrocardiogram data;
A U-wave segment point detection step of detecting a point on the waveform of the measurement electrocardiogram corresponding to the detected feature point of the U loop as a segment point of the U-wave in the measurement electrocardiogram;
An electrocardiogram data processing method comprising: In a computer in an electrocardiogram data processing device for detecting a U wave in a measurement electrocardiogram which is a scalar electrocardiogram measured using electrodes,
An electrocardiogram conversion function for generating second electrocardiogram data indicating a vector electrocardiogram configuration scalar electrocardiogram by converting the first electrocardiogram data indicating the measured electrocardiogram;
A U-loop feature point detection function for detecting a feature point of the U-loop in the vector electrocardiogram constituted by the vector electrocardiogram-constituting scalar electrocardiogram based on the generated second electrocardiogram data;
A U-wave segment point detection function for detecting a point on the waveform of the measurement electrocardiogram corresponding to the detected feature point of the U loop as a segment point of the U-wave in the measurement electrocardiogram;
ECG data processing program for realizing.