Electrocardiogram (E-lect-ro-car-dee-oh-gram), or ECG, is a way for doctors to find out how your heart is working. It does not hurt. The person testing you will put some sticky patches on your chest. Then they will connect wires to the patches. These are called electrodes (E-lek-trodes). Sometimes they’re called leads. These leads are hooked up to a machine. They will also put leads on your ankles and wrists.

You won’t need to do anything but lie still. You won’t feel anything while the person testing you runs the machine. It will only take about 10 or 15 minutes. At times, you may need to lie very still for about 15 seconds. This helps the doctors get the best “picture” of your heart’s electrical activity.