Electrocardiogram Sensor Sheet

Abstract

To provide an electrocardiogram sensor sheet which disposes four limb electrodes of an electrocardiogram in a relation of an Einthoven's equilateral triangle and has no mixture of drift of a base line caused by an abdominal electromyogram and breathing.SOLUTION: In an electrocardiogram sensor sheet, a sheet covering a subject precordial region with ground electrodes is provided with four limb electrodes for ML induction, a lower limb electrode leaking a right foot electrode and a left foot electrode by lead wire is disposed in a relation of an Einthoven's equilateral triangle, and is provided with precordial lead electrodes.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an electrocardiogram sensor sheet for performing electrocardiogram examinations. [Background technology]

[0002] Generally, a resting electrocardiogram test is performed using standard 12-lead (hereinafter referred to as STD lead) electrocardiograms, in which four limb electrodes, namely a right hand electrode (hereinafter referred to as RA electrode), a left hand electrode (hereinafter referred to as LA electrode), a right foot electrode (hereinafter referred to as RF electrode), and a left foot electrode (hereinafter referred to as LF electrode), and chest electrodes C1 to C6 are attached to the V1 to V6 regions of the chest, as shown in FIG. 5 (see Non-Patent Document 1).

[0003] The RF electrode is a body earth electrode (hereafter referred to as the N electrode), and the LF electrode is a lower limb electrode (hereafter referred to as the F electrode). The shape connecting the RA electrode, LA electrode, and LF electrode forms an Einthoven equilateral triangle15. In electrocardiogram examinations, a comprehensive diagnosis is made by interpreting electrocardiogram waveforms from bipolar limb leads (leads I, II, and III), unipolar limb leads (leads aVR, aVL, and aVF), and unipolar chest leads (leads V1 to V6) (see Non-Patent Document 1).

[0004] There is an electrocardiogram sensor sheet that allows the above-mentioned multiple electrodes to be attached to predetermined positions all at once (Patent Documents 1 and 2). This covers the anterior chest of the subject 5, allowing multiple electrodes to be attached quickly and accurately to the specified locations, and since it is connected to the electrocardiograph via a connector, there is no risk of incorrect connection of the electrodes and lead wires, making it an extremely convenient and useful tool for electrocardiogram tests in emergencies. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP2017-023882A [Patent Document 2] Special Publication No. 11-513854 [Non-patent literature]

[0006] [Non-Patent Document 1] Electrocardiogram: Lead Method, [Retrieved March 1, 2022], Internet http: / / www.udatsu.vsl.jp / ecg-lead.htm [Non-Patent Document 2] Clinical electrocardiographic comparison of standard 12 leads and Mason-Likar leads, [Retrieved March 1, 2022], Internet https: / / www.jstage.jst.go.jp / article / jse1981 / 7 / 2 / 7_2_205 / _pdf / -char / ja Summary of the Invention [Problem to be solved by the invention]

[0007] In conventional electrocardiogram sensor sheets, the electrodes of the sheet 10 are arranged in the Mason-Likar leads (hereinafter referred to as ML leads) as shown in Figure 2 in order to quickly and accurately attach the electrodes to predetermined locations on the anterior chest of the subject 5. ML leads are an electrode attachment method for exercise stress electrocardiogram testing, and are a modified 12-lead method in which the limb electrodes of STD leads are moved to the trunk. The unique feature is that abdominal electromyograms and baseline drift due to breathing are not mixed into the limb lead electrocardiogram waveforms.

[0008] On the other hand, Non-Patent Document 2 states that care must be taken when interpreting the ML lead ECG waveform because the ECG waveforms of leads II, III and aVF are enhanced compared to the STD lead ECG waveform as shown in Figures 6 to 8.

[0009] The basic principle for interpreting electrocardiogram waveforms is that they are derived from Einthoven's equilateral triangle. In other words, the limb electrodes are arranged in Einthoven's equilateral triangle as shown in Figure 3-D1, and the limb lead ECG waveforms that are displayed can be interpreted. However, when the limb electrodes are attached in Einthoven's equilateral triangle, the F electrode is attached directly above the abdomen, and the limb lead ECG waveforms that are displayed are significantly contaminated by abdominal electromyograms and baseline drift due to breathing, making it very difficult to interpret the ECG waveform.

[0010] In order to solve the above problems, the present invention provides an inexpensive electrocardiogram sensor sheet that modifies and improves the arrangement of the limb electrodes that are arranged in the ML lead on a conventional electrocardiogram sensor sheet, and depicts electrocardiogram waveforms derived from Einthoven's equilateral triangle, without interference from abdominal electromyograms or baseline drift due to breathing in the limb lead electrocardiogram waveforms. [Means for solving the problem]

[0011] FIG. 1-A1 is a structural diagram of the present invention, in which the limb electrodes and chest electrodes are arranged in ML leads on a sheet 10 having an N electrode, and the RF and LF electrodes are leaked by a conductor 20 having an intermediate terminal 21, which serves as a Goldberger indifferent electrode.

[0012] In the present invention, the anterior chest of subject 5 is covered as shown in FIG. 1-A2, the RA electrode is attached near the inside of the deltoid muscle in the right subclavian fossa, and the LA electrode is attached near the inside of the deltoid muscle in the left subclavian fossa, and the RF electrode and LF electrode are attached to the costal arches symmetrically on the left and right sides so that the intermediate terminal 21, the RA electrode, and the LA electrode form an Einthoven's equilateral triangle 15. As a result, the intermediate terminal 21, which was the indifferent electrode of Goldberger, becomes the F electrode.

[0013] The present invention is connected to an electrocardiograph by connecting the intermediate terminal 21 to the left foot lead, the N electrode to the right foot lead, the RA electrode to the right hand lead, and the LA electrode to the left hand lead, and further connecting the chest C1 to C6 electrodes (see Figures 1, 2, and 5) to the corresponding chest leads via connectors. Effect of the Invention

[0014] The limb lead electrocardiogram waveforms depicted in the present invention are electrocardiogram waveforms derived from Einthoven's equilateral triangle, and are free of abdominal electromyogram or baseline drift due to respiration, resulting in a readable 12-lead electrocardiogram waveform. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is an explanatory diagram of the electrocardiogram sensor sheet of the present invention. A1 is an external view of the electrocardiogram sensor sheet of the present invention. A2 is an embodiment of the electrocardiogram sensor sheet of the present invention worn by a subject. [Diagram 2] B1 is an external view of a conventional electrocardiogram sensor sheet. B2 is a diagram of a conventional electrocardiogram sensor sheet worn by a subject. [Diagram 3] Schematic diagram of different limb electrode attachments D1 is an Einthoven equilateral triangle diagram D2 is a non-Einthoven equilateral triangle diagram of the ML lead method D3 is an Einthoven equilateral triangle diagram of the present invention [Figure 4] E1 is a vector component diagram of each limb electrode for the cardiac electromotive force vector H. E2 is a vector component diagram of the F electrode leaking the LF electrode and RF electrode. [Diagram 5] Electrode placement for STD lead ECG and schematic diagram of Einthoven's equilateral triangle [Figure 6] List of limb lead ECG waveforms by limb electrode placement [Figure 7] Expanded table of ECG waveforms for leads II and III according to limb electrode placement [Figure 8] Expanded table of aVF lead ECG waveforms by limb electrode placement DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] The present invention provides an electrocardiogram sensor sheet in which the limb electrodes arranged in the ML lead in a conventional electrocardiogram sensor sheet are modified and improved to be arranged in Einthoven's equilateral triangle 15, and this modified and improved arrangement is explained in FIG. 3.

[0017] FIG. 3 is a schematic diagram of different limb electrode attachments, in which FIG. 3-D1 shows Einthoven's equilateral triangle, FIG. 3-D2 shows ML leads, and FIG. 3-D3 shows a schematic diagram of the present invention. In both cases, the RA electrode was placed near the medial side of the deltoid muscle in the right subclavian fossa, and the LA electrode was placed near the medial side of the deltoid muscle in the left subclavian fossa.

[0018] Fig. 3-D1 is a schematic diagram of the state in which the limb electrodes are attached to the anterior chest of a subject 5 in the form of an Einthoven equilateral triangle 15. In this case, the F electrode is attached directly above the abdominal muscles, so that the limb lead ECG waveform is significantly mixed with the electromyogram of the abdominal muscles and baseline drift due to breathing, making it difficult to interpret the ECG waveform.

[0019] FIG. 3-D2 is a schematic diagram of a state in which four limb electrodes are attached to the anterior chest of subject 5 for ML leads. The ML lead is a modified 12-lead in which the limb electrodes of the STD lead are moved to the trunk, with the LF electrode attached to the left costal arch and the RF electrode attached to the right costal arch. When the RA, LA, and LF electrodes of the ML lead are attached, they form a non-Einthoven equilateral triangle16, and the electrocardiogram waveforms of leads II and III and aVF are depicted larger than those of the STD lead. This means that care must be taken when interpreting the electrocardiogram waveforms, as described in Patent Document 2.

[0020] FIG. 3-D3 is a schematic diagram showing a state in which the four limb electrodes of the present invention are attached to the anterior chest of a subject 5. FIG. In the present invention, an F electrode was created using an RF electrode and an LF electrode in order to arrange the limb electrodes (FIG. 3-D2) arranged in the ML lead in the Einthoven's equilateral triangle 15 arrangement shown in FIG. 3-D1.

[0021] The F electrode of the present invention is based on Goldberger's augmented unipolar limb lead described in Non-Patent Document 1, and the RF and LF electrodes of the limb electrodes placed in the ML lead are leaked via a conductor 20 having an intermediate terminal 21, with the intermediate terminal 21 serving as Goldberger's indifferent electrode.

[0022] Furthermore, in order to change the intermediate terminal 21 from a Goldberger indifferent electrode to an F electrode, the RF electrode and the LF electrode are attached to both costal arches located (√3 / 2) × (length between the AR electrode and the LA electrode in cm) below the positions of the AR electrode and the LA electrode so that the intermediate terminal 21, the RA electrode, and the LA electrode form an Einthoven equilateral triangle 15. For example, if the distance from the AR electrode to the LA electrode is 30 cm, the electrodes will be attached approximately 26 cm below both costal arches.

[0023] In the above manner, the intermediate terminal 21 is the Goldberger indifferent electrode, which serves as the F electrode. In other words, the present invention is an electrocardiogram sensor sheet that does not require the F electrode to be attached to the abdomen, and the waveforms depicted from the RA electrode, LA electrode, and F electrode are derived from Einthoven's equilateral triangle and are readable electrocardiogram waveforms that are not contaminated by abdominal electromyograms or baseline drift due to breathing.

[0024] FIG. 4 is an explanatory diagram of the vector components of the F electrode relative to the cardiac electromotive force vector H. FIG. 4-E1 is a schematic diagram of vector components of the cardiac electromotive force vector H of each limb electrode when the limb electrodes are attached to the anterior chest of subject 5 via ML leads.

[0025] FIG. 4-E2 is a schematic diagram of vector components of the cardiac electromotive force vector H of the F electrode of the present invention. The vector components of the RF electrodes are (-x,y) and the vector components of the LF electrodes are (x,y). In the present invention, the RF electrode and the LF electrode are leaked via a conductor 20 having an intermediate terminal 21, so that the vector component of the intermediate terminal 21 with respect to the cardiac electromotive force vector H is (-x, y) + (x, y) = (0, y), and the vector component x of the cardiac electromotive force vector H is cancelled out, resulting in a lower limb electrode that captures only the vector component y.

[0026] Regarding the connection of the present invention to an electrocardiograph, the intermediate terminal 21 is connected to the left foot lead, the N electrode to the right foot lead, the RA electrode to the right hand lead, the LA electrode to the left hand lead, and the C1 to C6 chest electrodes are connected to the C1 to C6 chest leads of the electrocardiograph via connectors.

[0027] Figure 6 is a table comparing limb lead electrocardiogram waveforms according to the limb electrode attachment. In the three types of limb electrode attachment other than STD, the RA and LA electrodes are all in the same position, as shown in Figure 3. As a result, the same ECG waveforms are obtained in leads I, aVR, and aVL. Below, we will explain the ECG waveforms of limb leads II, III, and aVF related to the F electrode.

[0028] Figure 7 is a comparative table showing enlarged electrocardiogram waveforms of leads II and III according to electrode placement. The lead II electrocardiogram waveform when the electrode of the present invention was attached was closest to that when the equilateral triangle electrode of Einthoven was attached. As described in Non-Patent Document 2, the electrocardiogram waveform when an ML lead electrode is attached depicts a larger waveform than when an STD lead electrode is attached.

[0029] Figure 8 is a comparative table of ECG waveforms enlarged by aVF lead according to electrode placement. The difference in electrocardiogram waveforms between different electrode attachments is slight, but the electrocardiogram waveform obtained with the electrode attachment of the present invention is closest to that obtained with the equilateral triangular electrode attachment of Einthoven. The electrocardiogram waveform when the ML lead electrode is attached is larger than when the STD lead electrode is attached.

[0030] As described above, the present invention is an electrocardiogram sensor sheet with a modified and improved arrangement of electrodes compared to conventional electrocardiogram sensor sheets, and produces an electrocardiogram waveform in which the limb electrodes are arranged in an Einthoven's equilateral triangle. Since the F electrode is not attached to the abdomen, there is no interference with abdominal electromyograms or baseline drift due to breathing, and the electrocardiogram waveform that is displayed is easy to read. When only the limb lead ECG waveforms are to be visualized, the chest electrodes C1 to C6 are deleted. [Industrial Applicability]

[0031] The present invention contributes to the development of emergency medical care and sports medicine. [Explanation of symbols]

[0032] 5 Subjects 10 Sheets 15 Einthoven's equilateral triangle 16 Non-Einthoven's equilateral triangle 20 Conductors 21 Intermediate terminals H Heart electromotive force F Lower limb electrode N Body earth electrode RA, LA, RF, LF Limb electrodes C1, C2, C3, C4, C5, C6 Chest electrodes

Claims

[Claim 1] An electrocardiogram sensor sheet in which limb electrodes consisting of a right hand electrode, a left hand electrode, a right foot electrode, and a left foot electrode are provided in an ML lead on a sheet covering the anterior chest of a subject and has an earth electrode, and the right hand electrode and the left hand electrode are arranged in the relationship of an Einthoven equilateral triangle by connecting the right foot electrode and the left foot electrode with a conductor, and a chest lead electrode is provided, and an indifferent electrode is formed in the middle between the right foot electrode and the left foot electrode by connecting the right foot electrode and the left foot electrode with a conductor, and the indifferent electrode, the right hand electrode, and the left hand electrode are arranged in the relationship of an Einthoven equilateral triangle, characterized in that the right hand electrode is located near the inside of the deltoid muscle in the right subclavian fossa, the left hand electrode is located near the inside of the deltoid muscle in the left subclavian fossa, the right foot electrode is located on the right costal arch, and the left foot electrode is located on the left costal arch.

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