Decoding ECG of the heart

The ECG interpretation allows to reliably detect abnormalities in cardiac activity by examining the curve with the image of the heart rhythm. An electrocardiogram is a study of the activity of the heart activity for a certain period of time. It reflects electrical processes in the cardiac muscle, such as depolarization-excitation, and repolarization-the restoration of myocardial cells. The electrocardiogram is produced transthoracally, that is, through the thorax, with the help of electrodes mounted on the surface of the skin with further recording of indications for a special device. Correct interpretation of the ECG provides an opportunity to visually establish an accurate diagnosis and, if necessary, determine a timely course of treatment.

The ECG consists of images of teeth, segments and intervals. Teeth of the cardiogram are the extreme points of the curve of the line, which are denoted by Latin letters characterizing the following indications: atrial contraction (P), ventricular contraction (Q, R, S) and ventricular relaxation (T). The "U" prong is impermanent and is rarely recorded. Segments are segments of a straight line connecting adjacent teeth. The most important is the decoding of the ECG In the PQ and ST segments. For example, isoline PQ is formed during the excitation delay in the atrioventricular (atrioventricular) node. Intervals are a combination of teeth and segments. The most important intervals of the ECG are the intervals PQ and Q-T.

Excitation in the myocardium of the cardiac ventricles is characterized by the appearance on the ECG of the complex QRS complex, since it is not only more massive than the atrial muscle but also has an interventricular septum. In the QRS complex, the sizes of the individual teeth are first evaluated . If the amplitude of the tooth is more than 5 millimeters, it is denoted by the large Latin letter Q, R, and S, when the amplitude of its movement is smaller, it is prescribed by the small letter q, r or s. Decoding ECG implies correct reading of the teeth. The tooth of R (r) is each upwards directed positive prong, which is part of the QRS complex. Any downward-directed negative tooth located before the tooth R is prescribed as Q (q), and located after the tooth R is the tooth S (s). The tooth Q characterizes the depolarization of the interventricular septum, with myocardial infarction it has an expanded and deeper significance. The tooth R shows the depolarization of the main mass of the myocardium, and the tooth S shows the activity of the atrial divisions of the interventricular septum.

Decoding of the cardiac ECG consists of five points of study indications:

1. An analysis of the rhythm of the heart and cardiac conduction. This analysis implies an assessment of the heart rate, determination of the heart rate (HR), the establishment of an excitatory source and the conductivity characteristic;

2. Determination of the axis of electrical impulses of the heart;

3. Atrial tooth probe P;

4. Study of the QRST complex;

5. Conclusion of ECG diagnostics.

Decoding of the electrocardiogram of a healthy human heart begins with a short atrial wave (ab), reflecting the change in ventricular capacity when blood arrives at the moment of systole-atrial contraction. In the ECG, this wave is behind the P-wave and then goes upward, showing the systole of the ventricles. This steep ascent (b-d) follows the Q-wave and moves to the horizontal position (D-e). During the relaxation of the left ventricle and the reduction in pressure in it, the curve drops sharply downward (e-g), point g correlates with the opening of the mitral valve and the influx of blood into the ventricles. On the contraction wave, point c, which corresponds to the strained state of the mitral valve, and point f corresponding to the closure of the aortic valve are located. Following the systolic wave, a ventricular filling wave (g-h) is formed and slowly filled (k-a). Then follows the repeat of the ECG cycle of a healthy human heart.