Children's Hospital


Electrocardiography in Children

What is electrocardiography (ECG)?

Electrocardiography (ECG) is a simple, fast test to check the electrical activity of your child's heart as blood moves through it. Abnormal ECG results may mean there is a problem with your child's heart.

Why might my child need an ECG?

Some conditions which may cause changes in the ECG pattern include:

  • An enlarged heart. Conditions such as heart defects present at birth (congenital), problems with heart valves, high blood pressure, or heart failure may cause an enlarged heart.
  • Ischemia. This means less blood flows to the heart muscle because of fatty buildup in the arteries.
  • Conduction disorders. This means a problem with the heart's electrical system. The heart may beat too fast, too slow, or at an uneven rate.
  • Abnormal electrolytes. This means having too much or too little of some minerals (electrolytes) in the blood. The minerals include potassium, magnesium, and calcium.
  • Pericarditis. This is an inflammation or infection of the sac that surrounds the heart.
  • Chest injury. This could be from a car accident.

An ECG may also be done for other reasons. For example, the healthcare provider might want to look for problems during a checkup or physical exam, or before surgery or another procedure.

What are the risks of an ECG?

There are no risks associated with ECG.

How do I get my child ready for an ECG?

Your child does not need to do anything special for an ECG. The technician will explain what he or she is doing to your child.

What happens during an ECG?

An ECG can be done almost anywhere. The equipment is very compact and portable. The equipment used includes the ECG machine, skin electrodes, and lead wires. The wires attach the electrodes to the ECG machine.

An ECG takes about 5 to 10 minutes, including attaching and detaching electrodes.

An ECG typically includes the following steps:

  • Your child will lie flat on a table or bed. He or she will need to lie still and not talk during the procedure. Parents can usually be present in the room. 
  • The ECG technician will attach small plastic patches (electrodes) to your child's chest. One electrode will be attached to each arm and leg.
  • The lead wires will be attached to the electrodes.
  • The ECG machine is started. It will take only a few minutes for the test to be completed.
  • Once the test is done, the technician will disconnect the leads and remove the electrodes.

What happens after an ECG?

Your child's healthcare provider will look at the results. Depending on the results, your child's provider may order more tests or refer you to a pediatric cardiologist. This is a doctor with special training to treat heart problems in children.

Next steps

Before you agree to the test or the procedure for your child make sure you know:

  • The name of the test or procedure
  • The reason your child is having the test or procedure
  • The risks and benefits of the test or procedure
  • When and where your child is to have the test or procedure and who will do it
  • When and how will you get the results
  • How much will you have to pay for the test or procedure
Online Medical Reviewer: Bass, Pat F. III, MD, MPH
Online Medical Reviewer: MMI board-certified, academically affiliated clinician
Last Review Date: 2/24/2015
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