An electrocardiogram uses an electrocardiograph to record the electrical activity changes produced by the heart in each cardiac cycle from the body surface. It checks the electrical activity of the heart. Many diseases can be diagnosed by electrocardiogram. However, the diagnosis of ECG depends on the onset of the disease.

The heart is a three-dimensional structure. In order to reflect the electrical activity on different sides of the heart, electrodes are placed on different parts of the human body to record and respond to the electrical activity of the heart.

The measurement methods of the cardiac axis mainly include visual inspection, drawing and table lookup. The table below is a visual assessment of the direction of the cardiac axis. The heart is a three-dimensional structure composed of countless cardiomyocytes. During the depolarization and repolarization process of the heart, many galvanic vectors in different directions are generated. The electrocouple vectors in different directions are integrated into one vector to form the comprehensive ECG vector of the entire heart.

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Extended information

心electrogram generation Principle

The cardiomyocyte membrane is a semipermeable membrane. In the resting state, a certain number of positively charged cations are arranged outside the membrane, and the same number of negatively charged anions are arranged inside the membrane. The potential outside the membrane is higher than that inside the membrane. , called the polarization state. In the resting state, since myocardial cells in all parts of the heart are in a polarized state and there is no potential difference, the potential curve recorded by the current recorder is flat, which is the isoelectric line of the surface electrocardiogram.

Different leads are formed between two electrodes or between the electrodes and the central potential end, and are connected to the positive and negative poles of the electrocardiograph ammeter through the lead wires to record the electrical activity of the heart. A bipolar lead is formed between the two electrodes, one lead is positive and the other is negative.

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