What is it?

An electrocardiogram, or ECG, records the electrical activity of the heart. Sometimes this test is called an EKG.

Why is it done?

The test is used to check if the heart rate and rhythm are normal. An ECG also helps doctors determine whether your child has certain heart problems, including, but not limited to:

  • Heart enlargement
  • An electrolyte imbalance
  • Pericarditis
  • Other injuries to the heart

Also, ECGs are used to check the heart's status before and after heart surgery or a  cardiac catheterization  procedure.

They also can be used to check the function of a pacemaker and to check the effects of certain heart medicines.

How does it work?

An ECG is a noninvasive test. A number of electrodes (wires) are placed on the arms, legs and chest with stickers. The electrodes pick up tiny electrical signals from the heart and send them to a computer, which prints the information on a piece of paper for a doctor to interpret.

Up to 12 electrodes may be placed for an ECG to allow the doctor to "see" the heart's electrical activity from many different viewpoints at the same time. The resulting tracing looks like a group of wavy lines. Each of the waves on the ECG tells the doctor about the electrical conduction in a different part of the heart and can help to diagnose various heart defects and abnormalities.

An adult's heart rate should be between 50 and 100 beats per minute. A child can have a much faster rate - up to 180 beats per minute in an infant. The heart's rhythm is typically very regular, but in children it will often speed up and slow down rhythmically. The doctor will look for any abnormalities in the heart rhythm that might affect your child.

What happens during the test?

Your child will lie down on a table. A nurse or technician will attach up to 12 electrodes to your child's chest with stickers, and they will record the electrical signals from the heart.

How long does it take?

An ECG takes about 5 to 10 minutes.