Your doctor may order an electrocardiogram (also called an EKG or EKG) to check for signs of heart disease. This is a test where a technician records the electrical activity of a ticker using small electrodes attached to the skin of the chest, arms, and legs. ECG is fast, safe, and painless. With this test, your doctor will:

• check heart rate
• Check for insufficient blood supply to the heart muscle (this is called ischemia)
• heart attack diagnosis
• Check for abnormalities such as thickening of the heart muscle
• Check for electrolyte abnormalities such as high potassium or high or low calcium.

How should I prepare?

Here are some things you can do to prepare.

Do not use creams or lotions on oily or greasy skin on the day of the test. The electrodes do not touch the skin. Do not wear full socks as the electrodes must be attached directly to the foot.

Wear a dress that's easy to take off.

What happens during an electrocardiogram?

A technician attaches 10 electrodes with adhesive pads to the skin of the chest, arm, and leg. If you are male, you may need to shave your chest hair for a better connection.

During the test, the computer lies flat while it creates an image of an electric shock passing through the heart on graph paper. This is called a resting EKG, but the same test can be used to check the heart during exercise.

It takes about 10 minutes to attach the electrodes and complete the test, while the actual recording takes a few seconds. Your doctor can track your EKG pattern and compare it to future tests.

Types of ECG tests

In addition to the standard ECG, your doctor may recommend other types.

Holter monitor. This is a portable EKG that monitors the heart's electrical activity 24 hours a day for 1-2 days. Your doctor may recommend this if you suspect an irregular heartbeat, palpitations, or insufficient blood flow to your heart muscle. 

It is not as painful as a standard EKG. The monitor electrodes are attached to the skin. Once seated, you can go home and do all your normal activities except showering. Your doctor will ask you to keep a diary of what you do and any symptoms you notice.

Event tracking. If you have intermittent symptoms, your doctor may recommend this device. At the push of a button, it records and stores the heart's electrical activity for several minutes. You may need to wear it for weeks or months. Whenever symptoms occur, you should try to get a reading from the monitor. The information is sent to the doctor over the phone, and the doctor analyzes it.