Electrocardiography

Electrocardiogram (ECG or EKG)
An electrocardiogram (ECG or EKG) is the first test performed on the human heart. It helps to determine:
Heartbeat
Heart rate
Regularity of heartbeats
Tachycardia (rapid heartbeat) or bradycardia (slow heartbeat)
Ectopic or wandering beats
Acute and chronic heart attacks
An ECG can potentially indicate the likelihood of nearly any heart disease.