An electrocardiogram (ECG or EKG) measures the electrical activity of your heart. Small electrical sensors, called electrodes, are put on your skin to sense the electricity that began in your heart. These electrical signals are turned into a graph that can give your doctor an idea of whether your heart is beating normally.
How You Benefit
An EKG can help your doctor diagnose heart attacks, arrhythmias and other heart conditions, detect conditions that alter the body's balance of electrolytes (e.g., potassium and magnesium) or identify other problems like drug overdoses.
What to Expect
Learn more about electrocardiograms, including what to expect and when to call your doctor, at our online Health Library.