It is used to detect cardiac disorders like arrhythmias, conduction disturbances; myocardial ischemia etc.
It reveals other findings related to life-threatening metabolic disturbances like hyperkalemia or increased, susceptibility to sudden cardiac death (Example: QT prolongation syndrome).
It is used to study the rate of heartbeat, and cardiac disorders such as myocardial infarction (MI), coronary artery diseases etc.