Electrocardiogram analyzer, electrocardiogram analysis method and program

Abstract

To provide an electrocardiogram analyzer for allowing an analyst to easily determine whether or not a subject has paroxysmal tachycardia from an electrocardiogram of the subject.SOLUTION: An electrocardiogram analyzer 3 includes an acquisition unit 331 for acquiring electrocardiogram data of a subject, a first calculation unit 332 for calculating a first value corresponding to a difference between a heart rate in a first period before a predetermined time point and a heart rate in the first period after the time point in the electrocardiogram data, a second calculation unit 333 for calculating a second value corresponding to a variation in a heart rate in a second period after the time point in the electrocardiogram data, a determination unit 334 for determining whether or not a detection condition is satisfied, the detection condition including that the first value is larger than a first reference value and the second value is smaller than a second reference value, and a display control unit 335 causing an information terminal to display detection information representing that the subject may have paroxysmal tachycardia, on condition that the determination unit determines that the detection condition is satisfied.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an electrocardiogram analyzer, an electrocardiogram analysis method, and a program for analyzing an electrocardiogram. [Background technology]

[0002] Patent Document 1 discloses a system for determining the presence of arrhythmia based on whether the heart rate of a subject to be analyzed, such as a patient, exceeds a threshold value. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2006-524106 Summary of the Invention [Problem to be solved by the invention]

[0004] In some cases, subjects may experience paroxysmal tachyarrhythmia (hereinafter referred to as paroxysmal tachycardia), a condition in which the pulse suddenly becomes faster due to an abnormality in the electrical signals of the heart. Since subjects who experience paroxysmal tachycardia may experience symptoms such as palpitations, shortness of breath, and fainting, it is necessary to check whether or not paroxysmal tachycardia has occurred in the subject.

[0005] Conventionally, it has not been easy for medical professionals to find the location of paroxysmal tachycardia in the long-term electrocardiogram of a subject. When medical professionals visually find the location of paroxysmal tachycardia in an electrocardiogram, there is no particular standard, and they make a judgment based on past experience, which can lead to inconsistency in their judgment. In addition, if the period of a seizure is short, there is a risk that medical professionals will easily overlook the seizure. Even if the location of a high heart rate in an electrocardiogram is automatically detected, the location where the heart rate naturally increases due to exercise, etc. will also be detected, so it will take a lot of effort for medical professionals to determine whether paroxysmal tachycardia is occurring at each detected location.

[0006] The present invention has been made in consideration of these points, and has an object to make it easier to determine whether or not a subject has paroxysmal tachycardia from the subject's electrocardiogram. [Means for solving the problem]

[0007] The electrocardiogram analyzer of the first aspect of the present invention comprises an acquisition unit that acquires electrocardiogram data of a subject, a first calculation unit that calculates, in the electrocardiogram data, a first value corresponding to a difference between a heart rate in a first period before a predetermined time point and a heart rate in the first period after the predetermined time point, a second calculation unit that calculates, in the electrocardiogram data, a second value corresponding to a variation in heart rate in a second period after the predetermined time point, a determination unit that determines whether or not a detection condition is satisfied, including that the first value is greater than a first reference value and that the second value is less than a second reference value, and a display control unit that causes an information terminal to display detection information indicating that the subject may have paroxysmal tachycardia, on condition that the determination unit determines that the detection condition is satisfied.

[0008] The determination unit may determine whether or not the detection condition is satisfied, the detection condition further including a heart rate from the time point onwards being greater than a third reference value.

[0009] The determination unit may determine whether or not the detection condition is satisfied, the detection condition further including a state in which the second value is less than a second reference value for a predetermined period of time or more after the first value becomes greater than a first reference value.

[0010] The determination unit may identify consecutive sections in the electrocardiogram data in which it is determined that the detection condition is satisfied as seizure sections, and the display control unit may cause information indicating the seizure sections to be displayed on the information terminal.

[0011] The display control unit may cause the information terminal to display a starting point of the episode period in a graph showing time-dependent changes in heart rate or electrocardiogram waveform, which is generated based on the electrocardiogram data.

[0012] The display control unit may cause the information terminal to display a start point and an end point of the seizure period in the graph.

[0013] The display control unit may display on the information terminal a portion of a graph showing time-dependent changes in heart rate or electrocardiogram waveform generated based on the electrocardiogram data, where the determination unit has determined that the detection condition is satisfied, enlarged more than other portions of the graph.

[0014] The display control unit may cause the information terminal to display, in a graph showing time-dependent changes in heart rate or electrocardiogram waveform generated based on the electrocardiogram data, a point at which the determination unit determines that the detection condition is satisfied, in a display mode different from that of other points of the graph.

[0015] The display control unit may cause the information terminal to display the electrocardiogram waveform of a location where the determination unit has determined that the detection condition is satisfied in a graph showing the change over time in heart rate or electrocardiogram waveform generated based on the electrocardiogram data, in response to a selection by a user of the information terminal of the location.

[0016] The display control unit may cause the information terminal to display an electrocardiogram waveform at a location where the determination unit has determined that the detection condition is satisfied.

[0017] The display control unit may cause the information terminal to display an electrocardiogram waveform at the location where the judgment unit has determined that the detection condition is satisfied, and at least one of the electrocardiogram waveforms before and after the location where the judgment unit has determined that the detection condition is satisfied.

[0018] The display control unit may cause the information terminal to display a list of electrocardiogram waveforms at each of a plurality of locations at which the determination unit has determined that the detection condition is satisfied.

[0019] An electrocardiogram analysis method according to a second aspect of the present invention includes the steps of: acquiring electrocardiogram data of a subject, executed by a processor; calculating a first value in the electrocardiogram data corresponding to a difference between a heart rate in a first period before a predetermined time point and a heart rate in the first period after the time point; calculating a second value in the electrocardiogram data corresponding to a variation in heart rate in a second period after the time point; determining whether or not detection conditions are satisfied, including that the first value is greater than a first reference value and that the second value is less than a second reference value; and, if it is determined in the determining step that the detection conditions are satisfied, displaying detection information indicating that the subject may have paroxysmal tachycardia on an information terminal.

[0020] A program of a third aspect of the present invention causes a computer to function as an acquisition unit that acquires electrocardiogram data of a subject, a first calculation unit that calculates, in the electrocardiogram data, a first value corresponding to the difference between the heart rate in a first period before a predetermined time point and the heart rate in the first period after the predetermined time point, a second calculation unit that calculates, in the electrocardiogram data, a second value corresponding to the variation in the heart rate in a second period after the predetermined time point, a determination unit that determines whether or not a detection condition is satisfied, including the first value being greater than a first reference value and the second value being less than a second reference value, and a display control unit that causes an information terminal to display detection information indicating that the subject may have paroxysmal tachycardia, on condition that the determination unit determines that the detection condition is satisfied. Effect of the Invention

[0021] According to the present invention, it is possible to easily determine whether or not a subject has paroxysmal tachycardia from the subject's electrocardiogram. [Brief description of the drawings]

[0022] [Figure 1] 1 is a diagram for explaining an overview of an electrocardiogram analysis system according to an embodiment. FIG. [Diagram 2]1 is a block diagram of an electrocardiogram analysis system according to an embodiment. [Diagram 3] FIG. 13 is a diagram showing an exemplary graph of heart rates acquired by an acquisition unit. [Figure 4] 11 is a schematic diagram of an information terminal displaying a graph showing changes in heart rate over time as detected information. FIG. [Diagram 5] FIG. 13 is a schematic diagram of an information terminal displaying an electrocardiogram waveform as detected information. [Figure 6] 4 is a flowchart showing an electrocardiogram analysis method executed by the electrocardiogram analyzer according to the embodiment. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] [Outline of the Electrocardiogram Analysis System S] 1 is a diagram for explaining an overview of an electrocardiogram analysis system S according to this embodiment. The electrocardiogram analysis system S includes an electrocardiograph 1, an information terminal 2, and an electrocardiogram analyzer 3. The electrocardiogram analysis system S may include a plurality of electrocardiographs 1 and a plurality of information terminals 2. The electrocardiogram analysis system S may also include other devices such as a server and a terminal.

[0024] The electrocardiograph 1 is a device that measures the electrocardiogram of a subject. The subject is, for example, a patient undergoing medical treatment, a subject in a clinical trial, etc. The electrocardiograph 1 is, for example, a 12-lead electrocardiograph, a Holter electrocardiograph, an implantable electrocardiograph, an event-type electrocardiograph, a patch-type electrocardiograph, etc., that measures the electrocardiogram of the subject by measuring potential while being worn on the wrist, palm, chest, etc. of the subject. The electrocardiograph 1 may also be other devices capable of measuring an electrocardiogram, such as a pacemaker, a defibrillator, or an intracardiac electrode.

[0025] The electrocardiograph 1 transmits electrocardiogram data indicating the measured electrocardiogram to the electrocardiogram analyzer 3 via the network N. The electrocardiogram data measured by the electrocardiograph 1 may be input to the electrocardiogram analyzer 3, for example, using a storage medium, without going through the network N.

[0026] The information terminal 2 is a computer used by a specific user. The user of the information terminal 2 is, for example, an analyst such as a doctor or a medical professional. The information terminal 2 has, for example, a display unit such as a liquid crystal display capable of displaying information received from the electrocardiogram analyzer 3, and an operation unit such as a keyboard and a mouse that accepts operations by the analyst.

[0027] The electrocardiogram analyzer 3 is a computer for analyzing electrical activity of the heart. The electrocardiogram analyzer 3 analyzes whether or not the subject may have paroxysmal tachycardia, for example, based on the electrocardiogram data received from the electrocardiograph 1. Paroxysmal tachycardia (also called paroxysmal tachycardia) is a paroxysmal and tachyarrhythmia in which the pulse suddenly becomes faster due to an abnormality in the electrical signals of the heart. In addition to paroxysmal and tachyarrhythmia, paroxysmal tachycardia also includes sustained ventricular tachycardia, which is a sustained arrhythmia.

[0028] An overview of the processing executed by the electrocardiogram analysis system S according to this embodiment will be described below. The electrocardiogram analyzer 3 acquires electrocardiogram data indicating the electrocardiogram of the subject measured by the electrocardiograph 1. The electrocardiogram analyzer 3 sets the time points at which each of the multiple heartbeats included in the electrocardiogram data occurs as target time points, and executes the following processing for each target time point. The electrocardiogram analyzer 3 may also use only a portion of the multiple heartbeats included in the electrocardiogram data (e.g., heartbeats every 3rd beat, heartbeats every 5th beat, etc.).

[0029] The electrocardiogram analyzer 3 calculates a change value (first value) in the electrocardiogram data corresponding to the difference between the heart rate in a first period before the target time and the heart rate in the first period after the target time. The first period is a period defined by a predetermined number of heart beats or a predetermined time. The change value is a value calculated from the electrocardiogram data, and is a value that indicates the degree to which the heart rate after the target time has increased based on the heart rate before the target time.

[0030] The electrocardiogram analyzer 3 calculates a variation value (second value) corresponding to the variation in the heart rate within a second period from the target time point in the electrocardiogram data. The second period is a period defined by a predetermined number of heart beats or a predetermined time. The second period is, for example, a period following the first period, or a period starting from the point in time when a predetermined time (5 seconds, 10 seconds, etc.) has elapsed after the first period or when a predetermined number of heart beats (5 beats, 10 beats, etc.) have occurred. The variation value is a value calculated from the electrocardiogram data, and is a value indicating the degree to which the heart rate has changed from the target time point onwards.

[0031] The electrocardiogram analyzer 3 determines whether or not a detection condition is satisfied, including the change value being greater than a first reference value and the variation value being less than a second reference value. That is, the electrocardiogram analyzer 3 determines that the detection condition is satisfied when the difference between the heart rate in a first period before the target time point and the heart rate in a first period after the target time point is large and the variation in the heart rate in a second period after the target time point is small, and determines that the detection condition is not satisfied otherwise.

[0032] If it is determined that the detection condition is satisfied, the electrocardiogram analyzer 3 causes the information terminal 2 to display detection information indicating that the subject may have paroxysmal tachycardia.

[0033] In this way, the electrocardiogram analysis system S detects locations in the electrocardiogram of the subject where paroxysmal tachycardia may be occurring, and displays information indicating that the subject may have paroxysmal tachycardia on the information terminal 2 used by the analyst according to the detection results. In this way, the electrocardiogram analysis system S can make it easier for the analyst to determine whether or not the subject has paroxysmal tachycardia from the electrocardiogram of the subject.

[0034] [Configuration of the electrocardiogram analysis system S] FIG. 2 is a block diagram of an electrocardiogram analysis system S according to this embodiment. In FIG. 2, arrows indicate main data flows, and data flows other than those shown in FIG. 2 may exist. In FIG. 2, each block indicates a functional configuration, not a hardware (device) configuration. Therefore, the blocks shown in FIG. 2 may be implemented in a single device, or may be implemented separately in multiple devices. Data may be exchanged between blocks via any means, such as a data bus, a network, or a portable storage medium.

[0035] The electrocardiogram analyzer 3 has a communication unit 31, a storage unit 32, and a control unit 33. The electrocardiogram analyzer 3 may be configured by connecting two or more physically separate devices by wire or wirelessly. The electrocardiogram analyzer 3 may also be configured by a cloud that is a collection of computer resources.

[0036] The communication unit 31 has a communication controller for transmitting and receiving data between the electrocardiograph 1 and the information terminal 2 via the network N. The communication unit 31 notifies the control unit 33 of data received from the electrocardiograph 1 and the information terminal 2 via the network N. In addition, the communication unit 31 transmits data output from the control unit 33 to the information terminal 2 via the network N.

[0037] The storage unit 32 is a storage medium including a ROM (Read Only Memory), a RAM (Random Access Memory), a hard disk drive, etc. The storage unit 32 stores in advance a program to be executed by the control unit 33. The storage unit 32 may be provided outside the electrocardiogram analyzer 3, in which case data may be exchanged between the storage unit 32 and the control unit 33 via a network.

[0038] The control unit 33 has an acquisition unit 331, a first calculation unit 332, a second calculation unit 333, a determination unit 334, and a display control unit 335. The control unit 33 is a processor such as a CPU (Central Processing Unit), and functions as the acquisition unit 331, the first calculation unit 332, the second calculation unit 333, the determination unit 334, and the display control unit 335 by executing a program stored in the storage unit 32. At least a part of the functions of the control unit 33 may be executed by an electric circuit. Also, at least a part of the functions of the control unit 33 may be realized by the control unit 33 executing a program executed via a network.

[0039] The electrocardiogram analysis method executed by the electrocardiogram analysis system S according to this embodiment will be described in detail below. The subject wears the electrocardiograph 1. The electrocardiograph 1 measures the electrocardiogram of the subject wearing the electrocardiograph 1. The electrocardiograph 1 transmits electrocardiogram data indicating the measured electrocardiogram to the electrocardiogram analyzer 3. The electrocardiograph 1 transmits the electrocardiogram data to the electrocardiogram analyzer 3 sequentially, or transmits electrocardiogram data for a predetermined period (e.g., 24 hours) collectively to the electrocardiogram analyzer 3.

[0040] In the electrocardiogram analysis device 3, the acquisition unit 331 acquires the electrocardiogram data of the subject transmitted by the electrocardiograph 1 via the communication unit 31, and stores the acquired electrocardiogram data in the memory unit 32 in association with identification information (ID: Identifier) ​​for identifying the subject.

[0041] The electrocardiogram analysis device 3 executes subsequent processing when a specified start operation is performed by the analyst on the information terminal 2, or automatically executes subsequent processing when the acquisition unit 331 acquires new electrocardiogram data.

[0042] The acquiring unit 331 acquires the heart rate of the subject at the time of each heartbeat from the acquired electrocardiogram data. For example, the acquiring unit 331 acquires a plurality of electrocardiogram waveforms generated by separating the electrocardiogram data for each beat, calculates an R-R interval (also called R-R), which is the interval between the positions of R waves in two consecutive electrocardiogram waveforms from the acquired electrocardiogram waveforms, and calculates the heart rate at each time point from the calculated R-R interval. The acquiring unit 331 may acquire the heart rate of the subject by other methods.

[0043] Fig. 3 is a diagram showing an exemplary graph of the heart rate acquired by the acquisition unit 331. In the graph shown in Fig. 3, the horizontal axis represents time in a predetermined unit (elapsed time based on a predetermined date and time, etc.), and the vertical axis represents the heart rate in a predetermined unit. For example, the unit of time is seconds, and the unit of the heart rate is beats per minute (bpm). Note that the graph shown in Fig. 3 shows the heart rate of a patient with paroxysmal tachycardia, and therefore includes a portion where the heart rate suddenly rises.

[0044] The acquiring unit 331 specifies a time point at which each of a plurality of heartbeats included in the electrocardiogram data occurred as a target time point P. The first calculating unit 332, the second calculating unit 333, and the determining unit 334 execute the following processes for each target time point P specified by the acquiring unit 331.

[0045] The first calculation unit 332 calculates a change value V1 (first value) corresponding to the difference between the heart rate in a first period T1 before the target time point P and the heart rate in the first period T1 after the target time point P in the electrocardiogram data. The first period T1 is a period defined by a predetermined number of heart beats or a predetermined time. The first period T1 is, for example, a period of 10 beats (10 heart beats), a period of 10 seconds, etc. The first period T1 is stored in advance in the storage unit 32, or is specified on the information terminal 2 by the analyst.

[0046] The change value V1 is a value calculated from electrocardiogram data, and is a value that indicates the degree to which the heart rate after the target time point P has increased based on the heart rate before the target time point P. The change value V1 is, for example, a value obtained by subtracting a representative value of the heart rate in the first period T1 immediately before the target time point P from a representative value (average value, median, etc.) of the heart rate in the first period T1 immediately after the target time point P. Furthermore, the change value V1 may be, for example, a rate (proportion) of an increase in the representative value of the heart rate in the first period T1 immediately after the target time point P, relative to the representative value of the heart rate in the first period T1 immediately before the target time point P. The first calculation unit 332 may calculate the change value V1 after excluding outliers that satisfy a predetermined condition from the heart rates in the first period T1.

[0047] The first calculation unit 332 may calculate the change value V1 from the electrocardiogram data to be another value that indicates the degree to which the heart rate has increased after the target time point P based on the heart rate before the target time point P, without being limited to the specific value shown here.

[0048] The second calculation unit 333 calculates a variation value V2 (second value) corresponding to the variation in the heart rate within a second period T2 after the target time point P in the electrocardiogram data. The second period T2 is a period defined by a predetermined number of heartbeats or a predetermined time. The second period T2 is, for example, a period of 10 beats (10 heartbeats) or a period of 10 seconds. The second period T2 is stored in advance in the storage unit 32, or is specified by the analyst on the information terminal 2. The second period T2 may be the same length as the first period T1, or may be a different length from the first period T1.

[0049] The variation value V2 is a value calculated from electrocardiogram data, and is a value that indicates the degree to which the heart rate has changed after the target time point P. The variation value V2 is, for example, the standard deviation or variance of the heart rate within a second period T2 immediately after the target time point P. The second calculation unit 333 may calculate the variation value V2 after excluding outliers that satisfy a predetermined condition from the heart rate within the second period T2.

[0050] The second calculation unit 333 may calculate the variation value V2 using the R-R interval instead of the heart rate. Since the R-R interval is the reciprocal of the heart rate, the variation of the R-R interval corresponds to the variation of the heart rate. For example, the second calculation unit 333 calculates the standard deviation or variance of the R-R interval within the second period T2 after the target time point P as the variation value V2. The second calculation unit 333 may calculate the variation value V2 after excluding outliers that satisfy a predetermined condition from the R-R intervals within the second period T2.

[0051] The second calculation unit 333 may calculate, from the electrocardiogram data, as the variation value V2, not limited to the specific values ​​shown here, but any other value that indicates the degree to which the heart rate has changed after the target time point P.

[0052] The determination unit 334 determines whether the change value V1 calculated by the first calculation unit 332 and the variation value V2 calculated by the second calculation unit 333 satisfy a predetermined detection condition. The detection condition is a condition for detecting the characteristics of paroxysmal tachycardia in the electrocardiogram data. The determination unit 334 acquires the detection condition stored in advance in the storage unit 32, for example.

[0053] The detection condition includes, for example, that the change value V1 is greater than a first reference value and that the variation value V2 is less than a second reference value. The determination unit 334 determines that the detection condition is satisfied when, for example, the change value V1 is greater than the first reference value and the variation value V2 is less than the second reference value, and determines that the detection condition is not satisfied when these conditions are not satisfied.

[0054] The first reference value is, for example, 20 beats / minute (when the change value V1 is the difference in heart rates). The second reference value is, for example, 5 beats / minute (when the variation value V2 is the standard deviation of the heart rates) or 20 milliseconds (when the variation value V2 is the standard deviation of the RR intervals). The first reference value and the second reference value are stored in advance in the storage unit 32, or are specified by the analyst in the information terminal 2. The first reference value and the second reference value are determined according to the definitions of the change value V1 and the variation value V2.

[0055] This allows the electrocardiogram analyzer 3 to automatically detect, in the electrocardiogram of the subject, a location where the heart rate increases suddenly and then continues to be high for a certain period of time, as a location where paroxysmal tachycardia may be occurring. When the heart rate of the subject increases naturally due to exercise or the like, the heart rate increases gradually and there is a large variability in the heart rate, so by using the change value V1 and the variability value V2, the electrocardiogram analyzer 3 can accurately detect locations where paroxysmal tachycardia may be occurring, distinguishing them from locations where the heart rate increases naturally.

[0056] The detection condition may further include that the heart rate after the target time point P is greater than a third reference value. The determination unit 334 determines that the detection condition is satisfied when, for example, the change value V1 is greater than the first reference value, the variation value V2 is less than the second reference value, and the heart rate after the target time point P is greater than the third reference value, and determines that the detection condition is not satisfied otherwise. The heart rate after the target time point P is, for example, the heart rate immediately after the target time point P, or a representative value (average value, median value, etc.) of the heart rate within a predetermined period (for example, the above-mentioned second period T2) immediately after the target time point P.

[0057] The third reference value is, for example, 130 beats / min. The third reference value is stored in advance in the storage unit 32, or is specified by the analyst at the information terminal 2. This allows the electrocardiogram analyzer 3 to detect a location where paroxysmal tachycardia may be occurring, using the height of the heart rate as a condition in addition to the difference and variation in the heart rates.

[0058] The detection condition may further include a state in which the variation value V2 is less than the second reference value after the change value V1 becomes greater than the first reference value (or a state in which the variation value V2 is less than the second reference value and the heart rate after the target time point P is greater than the third reference value) continuing for a predetermined duration or more. The determination unit 334 determines that the detection condition is satisfied, for example, when the state in which the variation value V2 is less than the second reference value after the change value V1 becomes greater than the first reference value continues for a predetermined duration or more, and determines that the detection condition is not satisfied if this is not the case.

[0059] The duration is, for example, 60 seconds. The duration is stored in advance in the storage unit 32, or is specified by the analyst at the information terminal 2. This allows the electrocardiogram analyzer 3 to detect a location where paroxysmal tachycardia may be occurring, on the condition that a rapid increase in heart rate is followed by a prolonged high heart rate in the electrocardiogram of the subject.

[0060] The detection condition may further include that the steepness indicating the steepness of the change in the heart rate before and after the target time point P is greater than a fourth reference value. The steepness is, for example, a value (difference) obtained by subtracting the heart rate at the time point immediately before the target time point P from the heart rate at the target time point P. The steepness may also be, for example, a value of the slope of the graph of the heart rate at the target time point P. The determination unit 334 determines that the detection condition is satisfied when, for example, the change value V1 is greater than the first reference value, the variation value V2 is less than the second reference value, and the steepness is greater than the fourth reference value, and otherwise determines that the detection condition is not satisfied. In this way, the electrocardiogram analyzer 3 can detect a location where paroxysmal tachycardia may occur, based on the condition that the heart rate has suddenly increased in addition to the difference and variation in the heart rates.

[0061] The determination unit 334 specifies a continuous section in the electrocardiogram data where it is determined that the detection condition is satisfied as an attack section. For example, the determination unit 334 determines the target time point P where it is determined that the detection condition is satisfied as the start point of the attack section. When the determination unit 334 determines that the detection condition is satisfied at a plurality of continuous target time points P, the determination unit 334 may determine the target time point P where the change value V1 calculated by the first calculation unit 332 is the highest among the plurality of target time points P as the start point of the attack section. For example, the determination unit 334 determines the time point where the heart rate becomes equal to or lower than a predetermined reference value (for example, the above-mentioned third reference value) after the start point as the end point of the attack section. When there are a plurality of continuous sections in the electrocardiogram data where it is determined that the detection condition is satisfied, the determination unit 334 may specify a plurality of attack sections.

[0062] The display control unit 335 causes the information terminal 2 to display detection information indicating that the subject may have paroxysmal tachycardia, on condition that the determination unit 334 determines that the detection condition is satisfied for any of the target time points P. On the other hand, the display control unit 335 may cause the information terminal 2 to display information indicating that the subject may not have paroxysmal tachycardia, on condition that the determination unit 334 determines that the detection condition is not satisfied for any of the target time points P.

[0063] The display control unit 335 transmits, for example, detection information for displaying information indicating one or more seizure periods identified by the determination unit 334 to the information terminal 2 via the communication unit 31. The detection information includes, for example, the electrocardiogram data of the subject acquired by the acquisition unit 331, the heart rate of the subject at each time point acquired by the acquisition unit 331, and the start point and end point of the seizure period identified by the determination unit 334. The information terminal 2 receives the detection information transmitted by the electrocardiogram analyzer 3, and displays the received detection information on the display unit.

[0064] FIG. 4 is a schematic diagram of the information terminal 2 displaying a graph of the heart rate as the detection information. The display control unit 335, for example, displays a predetermined character string ("attack section 1" and "attack section 2" in FIG. 4) indicating one or more attack sections in a graph showing the time change of the heart rate. The heart rate graph is, for example, a graph in which the horizontal axis is a predetermined unit of time (elapsed time based on a predetermined date and time, etc.) and the vertical axis is a predetermined unit of heart rate. In addition, the display control unit 335, for example, displays symbols ("start" arrows and "end" arrows in FIG. 4) indicating the start and end points of one or more attack sections in the heart rate graph. This allows the electrocardiogram analyzer 3 to notify the analyst of a period in which paroxysmal tachycardia may have occurred in the subject.

[0065] Furthermore, the display control unit 335 may cause the information terminal 2 to display, in a display mode different from that of other parts of the heart rate graph, a portion (such as a range from the start point to the end point of an episode section) where the determination unit 334 has determined that the detection condition is satisfied. The display mode is, for example, the color, pattern, or type of the points, lines, or background that constitute the graph. This allows the electrocardiogram analyzer 3 to easily enable the analyst to visually distinguish periods in which the subject may have experienced paroxysmal tachycardia.

[0066] Furthermore, the display control unit 335 may display on the information terminal 2 a portion of the graph of the heart rate where the determination unit 334 has determined that the detection condition has been satisfied (such as a range from the start point to the end point of the seizure section) in an enlarged manner compared to other portions of the graph. For example, the display control unit 335 may enlarge and display the portion where the determination unit 334 has determined that the detection condition has been satisfied by making the unit of the horizontal axis (time) smaller than the other portions. The display control unit 335 may display a non-enlarged portion and an enlarged portion in one graph, or may display a non-enlarged graph ("overall view" in FIG. 4) and an enlarged graph ("enlarged view" in FIG. 4) separately. This allows the electrocardiogram analyzer 3 to make it easier for the analyst to analyze the tendency of the heart rate during a period in which the subject may have experienced paroxysmal tachycardia.

[0067] In addition, the display control unit 335 may display on the information terminal 2, instead of the graph showing the change in heart rate over time as illustrated in FIG. 4, information showing the seizure period and the start and end points of the seizure period in a graph showing the change in electrocardiogram waveform over time, and may also display on the information terminal 2 an enlarged view of the portion of the graph where the determination unit 334 has determined that the detection condition has been satisfied.

[0068] The display control unit 335 may cause the information terminal 2 to display, instead of or in addition to the graph of the heart rate, an electrocardiogram waveform at a point where the determination unit 334 has determined that the detection condition is satisfied. Fig. 5 is a schematic diagram of the information terminal 2 displaying an electrocardiogram waveform as detection information.

[0069] The display control unit 335 generates a plurality of electrocardiogram waveforms by, for example, separating the electrocardiogram data for each beat by a known process. The display control unit 335 causes the information terminal 2 to display the electrocardiogram waveform at the point where the determination unit 334 determines that the detection condition is satisfied. The electrocardiogram waveform at the point where the determination unit 334 determines that the detection condition is satisfied is, for example, one or more electrocardiogram waveforms immediately after the target time point P, or one or more electrocardiogram waveforms at a time point when a predetermined time (5 seconds, 10 seconds, etc.) has elapsed since the target time point P. This allows the electrocardiogram analyzer 3 to make it easier for the analyst to analyze the tendency of the electrocardiogram waveform during a period when the subject may have experienced paroxysmal tachycardia.

[0070] The display control unit 335 may also display, on the information terminal 2, at least one of the electrocardiogram waveforms before and after the point at which the determination unit 334 determines that the detection condition is satisfied. The electrocardiogram waveform before the point at which the determination unit 334 determines that the detection condition is satisfied is, for example, one or more electrocardiogram waveforms immediately before the start point of the seizure section, or one or more electrocardiogram waveforms at a time point a predetermined time (5 seconds, 10 seconds, etc.) before the start point of the seizure section. The electrocardiogram waveform after the point at which the determination unit 334 determines that the detection condition is satisfied is, for example, one or more electrocardiogram waveforms immediately after the end point of the seizure section, or one or more electrocardiogram waveforms at a time point a predetermined time (5 seconds, 10 seconds, etc.) after the end point of the seizure section. This allows the electrocardiogram analyzer 3 to easily allow the analyst to compare the difference between the electrocardiogram waveforms before and after the time point at which it is detected that the subject may have had paroxysmal tachycardia.

[0071] 5, the display control unit 335 may cause the information terminal 2 to display a list of electrocardiogram waveforms at each of the multiple locations where the determination unit 334 has determined that the detection condition is satisfied. The display control unit 335 may further cause the information terminal 2 to display, for each of the multiple locations, at least one of the electrocardiogram waveforms before and after the location. In this way, when there is a possibility that the subject has experienced paroxysmal tachycardia multiple times, the electrocardiogram analyzer 3 allows the analyst to have an overview of the electrocardiogram waveforms for each occurrence.

[0072] The display control unit 335 may cause the information terminal 2 to display a list of electrocardiogram waveforms at some locations that satisfy a predetermined condition among the multiple locations at which the determination unit 334 has determined that the detection condition is satisfied. The display control unit 335 causes the information terminal 2 to display, for example, a list of electrocardiogram waveforms at a predetermined number of locations among the multiple locations at which the determination unit 334 has determined that the detection condition is satisfied, in descending order of duration or steepness described above. In this way, when there is a possibility that the subject has experienced paroxysmal tachycardia multiple times, the electrocardiogram analyzer 3 can show the analyst only electrocardiogram waveforms at locations that may be more important.

[0073] In response to an analyst of the information terminal 2 selecting a location where the determining unit 334 has determined that the detection condition is satisfied in the graph showing the time change in heart rate illustrated in Fig. 4, the display control unit 335 may cause the information terminal 2 to display the electrocardiogram waveform of that location illustrated in Fig. 5. This enables the electrocardiogram analyzer 3 to make it easier for the analyst to analyze both the heart rate graph and the electrocardiogram waveform of a location where paroxysmal tachycardia may have occurred in the subject.

[0074] Furthermore, the display control unit 335 may enlarge and display, within one screen displayed on the information terminal 2, a portion in the heart rate graph where the determination unit 334 has determined that the detection condition is satisfied, as exemplified in Fig. 4, and may also display the electrocardiogram waveform of that portion on the information terminal 2, as exemplified in Fig. 5. This allows the electrocardiogram analyzer 3 to make it easier for the analyst to analyze both the heart rate graph and the electrocardiogram waveform of the portion where paroxysmal tachycardia may have occurred in the subject.

[0075] [Flowchart of electrocardiogram analysis method] 6 is a diagram showing a flowchart of an electrocardiogram analysis method executed by the electrocardiogram analyzer 3 according to this embodiment. In the electrocardiogram analyzer 3, the acquisition unit 331 acquires the electrocardiogram data of the subject transmitted by the electrocardiograph 1 via the communication unit 31 (S11), and stores the acquired electrocardiogram data in the storage unit 32 in association with identification information for identifying the subject. The acquisition unit 331 acquires the heart rate of the subject at a predetermined time interval from the acquired electrocardiogram data (S12).

[0076] The acquiring unit 331 specifies a time point at which each of a plurality of heartbeats included in the electrocardiogram data occurred as a target time point P. The first calculating unit 332, the second calculating unit 333, and the determining unit 334 execute the following processes for each target time point P specified by the acquiring unit 331.

[0077] The first calculation unit 332 calculates a change value V1 (first value) corresponding to the difference between the heart rate in a first period T1 before the target time P and the heart rate in the first period T1 after the target time P in the electrocardiogram data (S13). The second calculation unit 333 calculates a variation value V2 (second value) corresponding to the variation in the heart rate in a second period T2 after the target time P in the electrocardiogram data (S14).

[0078] The determination unit 334 determines whether or not the change value V1 calculated by the first calculation unit 332 and the variation value V2 calculated by the second calculation unit 333 satisfy a predetermined detection condition (S15). When the determination unit 334 determines that the detection condition is satisfied for any of the target time points P (YES in S16), the display control unit 335 causes the information terminal 2 to display detection information indicating that the subject may have paroxysmal tachycardia (S17).

[0079] When the determination unit 334 determines that the detection condition is not satisfied for any of the target time points P (NO in S16), the electrocardiogram analyzer 3 ends the process. Here, the display control unit 335 may cause the information terminal 2 to display information indicating that the subject is unlikely to have paroxysmal tachycardia.

[0080] [Effects of the embodiment] Conventionally, there has been a problem that it is not easy for medical personnel to find a location where paroxysmal tachycardia occurs in a long-term electrocardiogram of an analyzed person. In response to this, the electrocardiogram analysis system S according to the present embodiment detects a location where paroxysmal tachycardia may occur in the electrocardiogram of the analyzed person, and displays information indicating that the analyzed person may have paroxysmal tachycardia on the information terminal 2 used by the analyst according to the detection result. As a result, the electrocardiogram analysis system S can reduce the analyst's time and effort in checking all of the electrocardiograms of the analyzed person, making it easier for the analyst to determine whether the analyzed person has paroxysmal tachycardia from the electrocardiogram of the analyzed person.

[0081] In addition, because the electrocardiogram analysis system S detects locations on the electrocardiogram where paroxysmal tachycardia may be occurring based on objective criteria, it is possible to reduce the influence of the analyst's experience on the electrocardiogram analysis results, and to reduce the risk that the analyst will overlook a seizure even if the seizure lasts for a short period of time.

[0082] In addition, when the subject's heart rate naturally increases due to exercise, etc., the heart rate increases gradually and there is a large variability in the heart rate. Therefore, by using the change value V1 and the variability value V2, the electrocardiogram analysis device 3 can accurately detect areas where paroxysmal tachycardia may be occurring and distinguish them from areas where the heart rate has naturally increased.

[0083] Although the present invention has been described above using the embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments, and various modifications and changes are possible within the scope of the gist of the present invention. For example, all or part of the device can be configured by distributing or integrating functionally or physically in any unit. In addition, new embodiments resulting from any combination of multiple embodiments are also included in the embodiments of the present invention. The effect of the new embodiment resulting from the combination combines the effect of the original embodiment.

[0084] The processor of the electrocardiogram analyzer 3 executes each step (process) included in the electrocardiogram analysis method shown in Fig. 6. That is, the processor of the electrocardiogram analyzer 3 executes a program for executing the electrocardiogram analysis method shown in Fig. 6, thereby executing the electrocardiogram analysis method shown in Fig. 6. Some of the steps included in the electrocardiogram analysis method shown in Fig. 6 may be omitted, the order of the steps may be changed, and multiple steps may be performed in parallel. [Explanation of symbols]

[0085] S Electrocardiogram Analysis System 1 Electrocardiograph 2. Information terminal 3. Electrocardiogram analyzer 31 Communications Department 32 Storage section 33 Control Unit 331 Acquisition Department 332 First Calculation Section 333 Second Calculation Section 334 Judgment section 335 Display control section

Claims

1. An acquisition unit for acquiring electrocardiogram data of a subject; a first calculation unit that calculates a first value corresponding to a difference between a heart rate in a first period before a predetermined time point and a heart rate in the first period after the predetermined time point in the electrocardiogram data; a second calculation unit that calculates a second value corresponding to a variation in heart rate within a second period from the time point in the electrocardiogram data; a determination unit that determines whether or not a detection condition is satisfied, the detection condition including that the first value is greater than a first reference value and the second value is less than a second reference value; a display control unit that displays, on an information terminal, detection information indicating that the subject may have paroxysmal tachycardia, on condition that the determination unit has determined that the detection condition is satisfied; An electrocardiogram analyzer having

2. The determination unit determines whether or not the detection condition is satisfied, the detection condition further including a heart rate from the time point onward being greater than a third reference value.

2. The electrocardiogram analyzer according to claim 1.

3. the determination unit determines whether or not the detection condition is satisfied, the detection condition further including a state in which the second value is less than the second reference value for a predetermined time or more after the first value becomes greater than a first reference value.

3. An electrocardiogram analyzer according to claim 1 or 2.

4. the determination unit identifies, as an attack period, a continuous period in the electrocardiogram data in which it is determined that the detection condition is satisfied; The display control unit causes the information terminal to display information indicating the seizure period.

3. An electrocardiogram analyzer according to claim 1 or 2.

5. the display control unit causes the information terminal to display a start point of the episode period in a graph showing a time change in the heart rate or the electrocardiogram waveform generated based on the electrocardiogram data.

5. An electrocardiogram analyzer according to claim 4.

6. the display control unit causes the information terminal to display a start point and an end point of the seizure period in the graph.

6. An electrocardiogram analyzer according to claim 5.

7. the display control unit causes the information terminal to display, in a graph showing a time change in the heart rate or the electrocardiogram waveform generated based on the electrocardiogram data, a portion determined by the determination unit that the detection condition is satisfied, in an enlarged manner compared to other portions of the graph.

3. An electrocardiogram analyzer according to claim 1 or 2.

8. the display control unit causes the information terminal to display, in a graph showing a time change in the heart rate or the electrocardiogram waveform generated based on the electrocardiogram data, a portion where the determination unit has determined that the detection condition is satisfied, in a display mode different from that of other portions of the graph.

3. An electrocardiogram analyzer according to claim 1 or 2.

9. the display control unit, in response to a user of the information terminal selecting a portion at which the determination unit has determined that the detection condition is satisfied in a graph showing a time change in the heart rate or the electrocardiogram waveform generated based on the electrocardiogram data, causes the information terminal to display the electrocardiogram waveform at the portion.

3. An electrocardiogram analyzer according to claim 1 or 2.

10. The display control unit causes the information terminal to display an electrocardiogram waveform at a location where the determination unit has determined that the detection condition is satisfied.

3. An electrocardiogram analyzer according to claim 1 or 2.

11. the display control unit causes the information terminal to display an electrocardiogram waveform at a location where the determination unit has determined that the detection condition is satisfied, and at least one of an electrocardiogram waveform before and after the location where the determination unit has determined that the detection condition is satisfied.

11. The electrocardiogram analyzer according to claim 10.

12. The display control unit causes the information terminal to display a list of electrocardiogram waveforms at each of a plurality of locations at which the determination unit has determined that the detection condition is satisfied.

11. The electrocardiogram analyzer according to claim 10.

13. The processor executes acquiring electrocardiogram data of a subject; calculating a first value corresponding to a difference between a heart rate in a first period before a predetermined time point and a heart rate in the first period after the time point in the electrocardiogram data; calculating a second value corresponding to a variation in heart rate within a second period from the time point in the electrocardiogram data; determining whether a detection condition is satisfied, the detection condition including the first value being greater than a first reference value and the second value being less than a second reference value; a step of displaying, on an information terminal, detection information indicating that the subject may have paroxysmal tachycardia, on condition that it is determined in the determining step that the detection condition is satisfied; The electrocardiogram analysis method comprises:

14. Computer, An acquisition unit for acquiring electrocardiogram data of a subject; a first calculation unit that calculates a first value corresponding to a difference between a heart rate in a first period before a predetermined time point and a heart rate in the first period after the predetermined time point in the electrocardiogram data; a second calculation unit that calculates a second value corresponding to a variation in heart rate within a second period from the time point in the electrocardiogram data; a determination unit that determines whether or not a detection condition is satisfied, the detection condition including that the first value is greater than a first reference value and the second value is less than a second reference value; a display control unit that displays, on an information terminal, detection information indicating that the subject may have paroxysmal tachycardia, on condition that the determination unit has determined that the detection condition is satisfied; A program that functions as a

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