Electrocardiogram

Electrocardiogram: A recording of the electrical activity of the heart.

An electrocardiogram is a simple, non-invasive procedure.

Electrodes are placed on the skin of the chest and connected in a specific order to a machine that, when turned on, measures electrical activity all overaround the heart.

Output is usually in the form of a long scroll of paper displaying a printed graph of activity.

Newer models output the data directly to a computer and screen, although a print-out may still be made.

To take a specific situation, the initial diagnosis of a heart attack is usually made by a combination of clinical symptoms and characteristic electrocardiogram (EKG) changes.

The EKG can detect areas of muscle ischemia (muscle deprived of oxygen) and/or dead tissue in the heart.