An electrocardiogram (ECG or EKG) is a test that measures the electrical signals in the heart. It is a simple, painless, and quick test that records the hearts electrical activity. Electrodes are placed on the chest to record the hearts electrical signals, which cause the heart to beat. The signals are shown as waves on an attached computer monitor or printer. ECG results can give a healthcare provider details about the following:

• Heart rate: An ECG can help identify an unusually fast heart rate (tachycardia) or an unusually slow heart rate (bradycardia) .

• Heart rhythm: An ECG can detect irregular heartbeats (arrhythmias) .

• Heart attack: An ECG can show evidence of a previous heart attack or detect signs of a current heart attack.

• Size and position of the hearts chambers: Sometimes information from an ECG can help measure the size and position of the hearts chambers.

An ECG is often the first test a healthcare provider will order if a patient has signs of a heart condition, such as chest pain, irregular heartbeats, shortness of breath, fatigue, or dizziness. It is a painless, noninvasive way to help diagnose many common heart problems.