An electrocardiogram (ECG/EKG) is a simple, non-invasive test that records the electrical activity of the heart. It is performed to detect underlying heart conditions when symptoms such as dizziness, weakness, confusion, shortness of breath, blurred vision, fainting, or heart palpitations are experienced.

A cardiologist may recommend an ECG to evaluate or diagnose the following conditions:
* Blockages or narrowing of the arteries that supply the heart, such as coronary artery disease.
* A history of a past heart attack.
* Irregular heart rhythms (arrhythmia).
* Monitoring the effectiveness of heart disease treatments, such as pacemakers.
* Identifying potential problems with heart valves.