An electrocardiogram records the electrical signals in your heart. It’s a common test used to detect heart problems and monitor the heart’s status in many situations. Electrocardiograms — also called ECGs or EKGs — are often done in a doctor’s office, a clinic or a hospital room. And they’ve become standard equipment in operating rooms and ambulances.
An ECG is a noninvasive, painless test with quick results. During an ECG, sensors (electrodes) that can detect the electrical activity of your heart are attached to your chest and sometimes your limbs. These sensors are usually left on for just a few minutes.
During the ECG
An electrocardiogram can be done in a doctor's office or hospital and is often performed by a technician. You may be asked to change into a hospital gown. Then you'll lie on an examining table or bed.
Electrodes — typically 10 — will be attached to chest and sometimes to your limbs. The electrodes are sticky patches applied to help record the electrical activity of your heart. Each one has a wire attached to a monitor. If you have hair on the parts of your body where the electrodes will be placed, the technician may shave the hair so that the patches stick.
You can breathe normally during the electrocardiogram. Make sure you're warm and ready to lie still. Moving, talking or shivering may distort the test results. A standard ECG takes a few minutes.
As you lie on the examination table or bed, the electrodes will record the impulses that make your heart beat. The impulses are recorded by a computer and displayed as waves on a monitor or printed on paper.
No special preparations are necessary for a standard electrocardiogram. Do tell your doctor about any medications and supplements you're taking because some can affect the results of your test.