An electrocardiogram (ECG or EKG) is a simple, painless, and quick test that records the electrical signals in the heart. Electrodes are placed on the chest, arms, and legs 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. An EKG is often the first test done if someone has signs of a heart condition, and it can help diagnose and monitor many types of heart conditions and their treatment.

During the test, the patient lies flat while a computer creates a picture, on a graph paper, of the electrical impulses that move through the heart. The test is quick, safe, and painless, and it can be done in a health care providers office, a clinic, or a hospital room. EKG machines are standard equipment in operating rooms and ambulances, and some personal devices, such as smartwatches, offer EKG monitoring.

ECG results can give a health care provider details about the heart rate, heart rhythm, and the strength and timing of the electrical signals passing through each part of the heart. The test can help identify an unusually fast heart rate (tachycardia) or an unusually slow heart rate (bradycardia) . Abnormal EKG results could be a sign of many heart-related conditions, including atrial fibrillation/flutter, heart attack, and thickened heart muscle.

An EKG is a very quick and pain-free test that can help a healthcare provider check the heart rhythm and evaluate the heart. The information from the EKG will help the provider decide what treatment would be best for the patient. The risks associated with EKG are minimal and rare.