JPS6112968Y2 - - Google Patents

Description

[Detailed description of the invention] This invention applies to the recorded electrocardiogram waveform, and each wave that appears as a waveform, and
This invention relates to a scale board for evaluating electrocardiogram waveforms that enables accurate, quick, and easy determination of cardiac function by measuring QRS axis deviation and the like.

Electrocardiograms are indispensable as one of the important diagnostic methods for heart disease, but determining the functional status of the heart from electrocardiogram waveforms requires complex calculations and the creation of converters. It is time consuming and troublesome. A considerable amount of skill is required to accurately judge the waveform of an electrocardiogram.

Previously, this electrocardiogram waveform judgment was carried out in the
Although it is published in the official gazettes of Jpn. Jpn. Examiner No. 716 and Jpn. Examiner No. 47-717 under the name of "Electrocardiogram QT Prolongation Judgment Ruler" and "Electrocardiogram Judgment Ruler," the one published in Jpn. Examiner No. 47-716 is a ruler that only judges the presence or absence of QT prolongation in the electrocardiogram waveform, and
The items published in this issue include pulse rate, PQ, and
This ruler can measure only the following items: prolongation, R wave, QT prolongation, and ST depression. The axis deviation measurement, which is essential for interpreting an electrocardiogram, was invented using Einthoven's equilateral triangle and was published in 1973.
There is an electrocardiogram mean electrical axis measuring device published in No. 63584, which consists of three transparent equilateral triangular plates fixed together with an angle indicator plate and a vertical plate between them; it is not a device for drawing on a flat surface, but rather a measuring instrument.

The applicant has researched and examined this electrocardiogram waveform from his professional standpoint as a physician.
We have developed a scale board that incorporates broader scales for several measurement elements that are important and indispensable for determining heart function, and allows them to be combined and arranged on one board. By using this scale board, cardiac function can be determined from electrocardiogram waveforms with great accuracy, speed, and ease.

The object of the present invention is to provide such a scale plate for evaluating electrocardiogram waveforms.

The scale plate for determining cardiac function based on electrocardiogram waveforms according to the present invention is capable of determining whether the QT interval is normal or shortened, as well as prolonging the QT interval. The QRS axis deviation measuring part, which is essential for the determination of The right axis deviation can be shown as an angle graduated on the circumference of the circle centered on the intersection point. That is, it is displayed on the scale plate as a scale part that allows accurate measurement of QRS axis deviation.

An electrocardiogram is a graph of potential difference that occurs with heart rate, and changes in potential difference during a cardiac cycle consist of a series of fluctuations that occur above and below a baseline, and each of these fluctuations is given a name. That is, the second
To explain the diagram, the first deflection is the P wave, the first negative deflection after the P wave is the Q wave, the first positive deflection is the R wave, the next negative deflection after the R wave is the S wave, and then These gentle curves are called T waves and U waves, respectively. The P wave represents the contraction of both atria, the QRS wave represents the cardiac action potential associated with the contraction of both ventricles, and the T wave represents the wave when the electrical excitation of both ventricles subsides. The meaning of the U wave is still unknown and is not recorded by guidance.

An embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a plan view showing the entire scale plate for determining electrocardiogram waveforms according to the present invention. The shape is a rectangular transparent plastic plate, and a heart rate scale 1 is provided along the upper edge of the plate.

Heart rate scale 1 is the RR of the waveform recorded on the electrocardiogram
The interval is measured based on the feeding speed of the electrocardiogram recording paper, and the heart rate per minute is measured. That is, since 1 mm horizontally on an electrocardiogram is normally 0.04 seconds, if the adjacent RR interval is measured in millimeters, the heart rate per minute can be calculated using the following formula. Heart rate scale 1 is created based on this calculation formula.

Heart rate = 60/RR x 0.04 In addition, a scale 3 is provided vertically in the center of the board to measure the height and depth of R waves and S waves, and the rise and fall of ST. There is. The scale 3 has its origin 0 set at the lower end and the thick line in the center.

Furthermore, on the left side of scale 3, the heart rate starts from 30.
Standard range calculated for RR intervals up to 150
A scale 2 for measuring the QT interval is provided, which is a diagram of the QT interval, with a scale indicating the heart rate on the left side, and a T section on the right side indicating a certain normal range of the QT interval. Also, on the right side of scale 3, there is a 60
Two straight lines that intersect at ° are displayed, and a scale is attached on the circumference centered at the intersection point to indicate the angle of the straight line drawn in the circumferential direction from the intersection point.
Alternatively, the right axis deviation can be expressed as an angle graduated on the circumference with the intersection as the center.
QRS axis deviation scale 4 is attached. Furthermore, a scale 5 indicating the length (cm) of the scale plate is provided along the lower edge of the plate.

Next, a method of actually measuring an electrocardiogram by applying the electrocardiogram waveform judgment scale plate A according to the present invention to an electrocardiogram will be explained.

First, let's talk about heart rate measuring scale 1. When you apply "↑RR x 3" displayed near the upper left corner of scale board A to the R wave of one heartbeat, three heartbeats to the right. The heart rate per minute is indicated from the top of the R wave (see Figure 3).Next, QTc interval scale 2 will be described. The QT interval is measured from the beginning of the Q wave to the end of the T wave, but the QT interval changes depending on the heart rate, and the faster the heart rate, the shorter it becomes, so it is usually corrected to a heart rate of 60 per minute using the following formula: do.

QTc=QT/√RR In other words, even in the same person, the QT interval varies depending on the heart rate, so it must be standardized. QT interval)
It is possible to set a normal value by setting QTc according to the above calculation, and the normal range is 0.36 to 0.42.

According to this scale board, QT in the standard range for various RR intervals (heart rate 30 to 150 in the example).
The interval is calculated and plotted, and a certain normal range is shown, so you can easily locate the beginning of the Q wave of two adjacent heartbeats on the QQ line by moving up and down the scale, without having to do any troublesome calculations. The QT interval can be measured simply by applying an electrocardiogram to the monitor. That is, if the end of the T wave is within the width of T on the scale, it is normal; if it exceeds the width of T to the right, it is QT prolongation, and if it is to the left of the width of T, it is QT shortening. (4th
(See figure) Next, we will explain how to measure the height and depth of the R wave, S wave, and ST section.This measurement scale is the scale 3 located in the center of the scale plate
As shown in FIG. 5, align the base line of the R wave or the deepest part of the S wave with the zero line at the bottom of scale 3,
The distance to the top of the R wave or the baseline of the S wave is measured and used. Abnormalities in the ST segment have rises and falls as shown in Figure 6, and in both cases, align the base line of the electrocardiogram with the thick line in the center of scale 3, and then rise and fall.
It reads the descent. This scale 3 was placed in the center of the scale plate A so that it could be used for measuring the QTc interval without moving the scale.

Finally, we will explain QRS axis deviation measurement.
In addition to the anatomical axis, the heart has an electrical axis, which is usually expressed by a vector composed of the absolute values of the deflections of the QRS complexes of the leads and the leads. It was done like this.

(a) Take the representative sum of the induced R-wave and S-wave deflections on the 〓 axis of the Einthoven equilateral triangle.

(b) Take the algebraic sum of the induced R-wave and S-wave deflections on the 3 axes.

(c) Draw a perpendicular line from each point.

(d) The straight line from the center of the equilateral triangle to the intersection of each perpendicular line represents the electrical axis, and read its direction with a protractor.

The measurement method using the scale plate of this invention is to calculate the sum of the R wave height (mm) and the Q (or S) wave height (mm) of the induction (above the baseline is considered below), and each of the values on the scale, Draw a perpendicular line at the line, and the point where the line connecting the center of the line intersects the outer circle is the degree of QRS axis deviation +
110° or more is called right axis deviation, and -30° or less is called left axis deviation.

In reality, for example, in the electrocardiogram shown in Figure 7, the algebraic sum of the R wave (+14 mm) and S wave (-3 mm) of the leads is (+14 mm) + (-3 mm) = +11,
The algebraic sum of the induced R wave (+14 mm) and S wave (-5 mm) is (+14 mm) + (-5 mm) = +9. Draw a perpendicular line at +11 and +9 on the scale plate of these values, and the +55° point where the line connecting the center and the center intersects the outer circle is the degree of QRS axis deviation. be. Further, in this embodiment, the right axis deviation and left axis deviation are shown by double curves.

What is shown in the reference figure is the QRS axis deviation measurement scale that has been used in the past. With this scale, the algebraic sum of the R-wave and S-wave deflections must be taken separately on each side of the equilateral triangle, making it difficult to draw. On the other hand, the QRS axis deviation part according to the present invention consists of two straight lines intersecting at 60° instead of an equilateral triangle.
This intersection point is the common starting point for the algebraic sum of the R wave and the S wave, and since this intersection point is connected to the intersection of the perpendicular line drawn from each point, it is a construction to find the direction of the axis. are concentrated around the intersection point, making it very easy to draw. Therefore, you can know the general direction of the axis from the beginning of the drawing, and if you include a straight line and a straight line perpendicular to it as a scale,
Angle can be measured without any special drawing.

The method of using the electrocardiogram waveform determination scale plate according to the present invention has been described above.

The effect of the scale plate for determining electrocardiogram waveforms according to the present invention is that when the scale plate is applied to the electrocardiogram waveform, each measurement element that is important and essential for determining cardiac function can be measured from the waveform appearing there. Based on these results, the functional state of the heart can be comprehensively determined extremely accurately, quickly, and easily, and this is an excellent advantage that could not be expected from conventional methods.

[Brief explanation of the drawing]

FIG. 1 is a front view of a scale plate for determining an electrocardiogram waveform according to the present invention, and FIG. 2 is an explanatory diagram showing the names of each wave in the electrocardiogram waveform. Figures 3 to 7 are explanatory diagrams showing examples of each scale. Figure 3 is an example of a heart rate measurement scale, Figure 4 is an example of a QTc interval measurement scale, and Figure 5 is an example of a QTc interval measurement scale. The figure is R
An example of the measurement scale for wave and S wave heights. Fig. 6 shows an example of the measurement scale for the ST portion. FIG. 7 is an example of a QRS axis deviation measurement scale. B...Transparent plastic electrocardiogram waveform judgment scale plate, 1... Heart rate measurement scale, 2...
QT interval measurement scale, 3... R wave, S wave height, depth ST rise, fall measurement scale, 4... QRS axis deviation measurement scale, 5... Scale indicating scale length.

Claims (1)

[Scope of utility model registration request] Heart rate measurement scale 1 that measures heart rate based on the RR interval of the waveform recorded on the electrocardiogram, and various
The QT interval in the standard range calculated for the RR interval is plotted, and the scale 2 for measuring the QT interval that shows a certain normal range, and the height and depth of the R wave and S wave, respectively, with the origin 0 at the appropriate position. A scale 3 that can measure the height, ST rise, and fall, and two straight lines that intersect at 60 degrees are provided, and on the circumference centered at the intersection,
The functional state of the heart can be comprehensively determined by combining the QRS axis deviation measurement part 4, which has a scale indicating the angle of a straight line drawn in the circumferential direction from the intersection point, on a transparent plate. A scale board for evaluating electrocardiogram waveforms.