Tests and Procedures

Electrocardiogram (ECG or EKG)

Results

Your doctor may discuss your results with you the same day as your electrocardiogram or at your next appointment.

If your electrocardiogram is normal, you may not need any other tests. If the results show an abnormality with your heart, you may need another ECG or other diagnostic tests, such as an echocardiogram. Treatment depends on what's causing your signs and symptoms.

Your doctor will review the information recorded by the ECG machine and look for any problems with your heart, including:

  • Heart rate. Normally, heart rate can be measured by checking your pulse. An ECG may be helpful if your pulse is difficult to feel or too fast or too irregular to count accurately. An ECG can help your doctor identify an unusually fast heart rate (tachycardia) or an unusually slow heart rate (bradycardia).
  • Heart rhythm. An ECG can show heart rhythm irregularities (arrhythmias). These conditions may occur when any part of the heart's electrical system malfunctions. In other cases, medications, such as beta blockers, cocaine, amphetamines, and over-the-counter cold and allergy drugs, can trigger arrhythmias.
  • Heart attack. An ECG can show evidence of a previous heart attack or one that's in progress. The patterns on the ECG may indicate which part of your heart has been damaged, as well as the extent of the damage.
  • Inadequate blood and oxygen supply to the heart. An ECG done while you're having symptoms can help your doctor determine whether chest pain is caused by reduced blood flow to the heart muscle, such as with the chest pain of unstable angina.
  • Structural abnormalities. An ECG can provide clues about enlargement of the chambers or walls of the heart, heart defects and other heart problems.

If your doctor finds any problems on your ECG, he or she may order additional tests to see if treatment is necessary.