An electrocardiogram, or EKG, is a simple, painless test that records the heart's electrical activity A technician attaches soft, sticky patches called electrodes to the skin of your chest, arms, and legs. The patches are about the size of a quarter. These electrodes are connected to the Electrocardiogram (EKG) machine.
Typically, 12 patches/electrodes are attached to detect your heart's electrical activity from many angles. To help the patches stick, the technician may have to shave areas of your skin.
After the patches are placed on your skin, you lie still on a table while the patches detect your heart's electrical signals. An EKG machine records these signals on graph paper or displays them on a screen. The entire test takes about 10 minutes.
The illustration shows the standard setup for an EKG. In figure A, a normal heart rhythm recording shows the electrical pattern of a regular heartbeat. In figure B, a patient lies in a bed with EKG electrodes attached to his chest, upper arms, and legs. A nurse watches the painless procedure
An EKG shows:
- How fast your heart is beating
- Whether the rhythm of your heartbeat is steady or irregular
- The strength and timing of electrical signals as they pass through each part of your heart.