What is it?

An exercise electrocardiogram (EKG or ECG) is a test that checks for changes in your heart while you exercise. Sometimes your doctor can only see heart problems during exercise or while you have symptoms.

This test is sometimes called an exercise EKG, stress test, or treadmill test.

Why is this test done?

You may need this test to check your heart's electrical activity. It can help find out if a heart problem is causing chest pain or find the cause of symptoms that happen during activity, such as dizziness or fainting. It can also help your doctor decide on the best treatment for certain heart problems.

How do you prepare for the test?

• Do not smoke or eat a heavy meal before this test.
• Wear flat, comfortable shoes (no bedroom slippers) and loose, lightweight shorts or sweatpants. Walking or running shoes are best.
• Tell your doctor ALL the medicines and natural health products you take. Some may increase the risk of problems during your test. Your doctor will tell you if you should stop taking any of them before the test and how soon to do it.

How is the test done?

You most likely will either walk on a treadmill or pedal a stationary bicycle.

You will have a blood pressure cuff on your upper arm. Small pads or patches (electrodes) will be placed, like stickers, on your skin on each arm and leg and on your chest. Your doctor may wrap your chest with an elastic band to keep the electrodes from falling off.

On the treadmill, you will start out slowly in a level or slightly inclined position. After certain periods of time, the speed and steepness of the treadmill will be increased so that you will be walking faster and at a greater incline.

On the stationary bicycle, you will pedal fast enough to keep a certain speed. After certain periods of time, the resistance will be increased, making it harder to pedal.

In both tests:

• Your EKG, heart rate, and blood pressure are recorded.
• You might be asked to use numbers to say how hard you are exercising. The higher the number, the harder you think you are exercising.
• The test will continue until:
  • You need to stop.
  • You have reached a target heart rate.
  • You have angina symptoms, such as chest pain or pressure.
  • You are very tired or very short of breath.
  • Your doctor feels you need to stop because of a change in your heartbeat or blood pressure.

After the test, you will be able to sit or lie down and rest. Your EKG and blood pressure will be checked for about 5 to 10 minutes.

What are the risks of the test?

• There is very little chance of having a problem from this test.
• Risks include:
  • Irregular heartbeats during the test.
  • Severe angina symptoms.
  • Fainting.
  • Falling.
  • Heart attack.
• No electricity passes through your body during the test. There is no danger of getting an electrical shock.

How long does the test take?

The test may take about 30 to 60 minutes.

What happens after the test?

• You will probably be able to go home right away. It depends on the reason for the test.
• You can go back to your usual activities right away.

When should you call for help?

Call 911 anytime you think you may need emergency care. For example, call if:

• You passed out (lost consciousness).
• You have been diagnosed with angina, and you have angina symptoms that do not go away with rest or are not getting better within 5 minutes after you take a dose of nitroglycerin.
• You have symptoms of a heart attack. These may include:
  • Chest pain or pressure, or a strange feeling in the chest.
  • Sweating.
  • Shortness of breath.
  • Nausea or vomiting.
  • Pain, pressure, or a strange feeling in the back, neck, jaw, or upper belly or in one or both shoulders or arms.
  • Light-headedness or sudden weakness.
  • A fast or irregular pulse.
  After you call 911, the operator may tell you to chew 1 adult-strength or 2 to 4 low-dose aspirin. Wait for an ambulance. Do not try to drive yourself.

Watch closely for changes in your health, and be sure to contact your doctor or nurse advice line if you have any problems.