An ECG can be performed to understand the electrical activity of the heart and to understand the presence or absence of heart disease (e.g. cardiac hypertrophy, heart attack, arrhythmia, etc.).
ECG utilizes an electrocardiograph to record from the surface of the body the graphic curves of the changes in electrical activity produced by the human heart during each cardiac cycle. The ECG is mainly composed of P waves, PR segments, QRS wave clusters, as well as ST segments, T waves and other wave segments, and has both limb leads and thoracic leads. If these waves are abnormal, cardiac diseases can be inferred based on the location, character, and leads of the abnormal waves.
Myocardial hypertrophy, myocardial ischemia, myocardial infarction, arrhythmia all have their specific ECG patterns, such as myocardial infarction in the acute stage can be seen pathologic Q wave, chest lead V1 ~ V3 suggests anterior interstitial myocardial infarction and so on.
If there is any cardiac discomfort or cardiac disease, you should cooperate with your doctor to actively carry out ECG examination.