1. Positive value for the diagnosis of arrhythmia and conduction disorder.
2. High accuracy in the diagnosis of myocardial infarction, which can not only confirm the presence of myocardial infarction, but also determine the lesion, location, range and evolution process of the infarction.
3. It is of great help in the diagnosis of atrioventricular hypertrophy, myocarditis, myocardiopathy, coronary artery insufficiency and pericarditis.
4. It can help to understand the effect of certain drugs (such as digitalis, quinidine, etc.) and electrolyte disorders on the myocardium.
5. As a time marker of electrical information, ECG is often used to measure the cardiac function such as phonocardiogram, echocardiography, anti-resistive flow chart, and other electrophysiological studies of the heart to determine the time.