Exercise Electrocardiogram: About This Test

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Inside of the heart

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 symptoms are present.

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 whether a heart problem is causing chest pain and can help your doctor decide on the best treatment for certain heart problems. It also helps find the cause of symptoms that happen during exercise or activity, such as dizziness, fainting, or rapid, irregular heartbeats.

How can 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 if:
    • You are taking any medicines.
    • You are taking medicine for an erection problem (such as Viagra). You may need to take nitroglycerin during this test, which can cause a serious reaction if you have taken a medicine for an erection problem within the past 48 hours.
    • You have had bleeding problems, or take aspirin or some other blood thinner.
    • You have joint problems in your hips or legs that may make it hard for you to exercise.
    • You have a heart valve problem.

What happens before the test?

  • Men are usually bare-chested during the test. Women may often wear a bra, T-shirt, or gown.
  • You may want to stretch your arm and leg muscles.
  • You may have to remove certain jewellery.
  • You will have a blood pressure cuff on your upper arm.
  • Small pads or patches (electrodes) will be attached to your skin on each arm and leg and on your chest. A special paste or pad may go between the electrode and your skin. Your doctor may wrap your chest with an elastic band to keep the electrodes from falling off.

What happens during the test?

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

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 your maximum heart rate. Heart rate is how many times your heart beats in a minute. Maximum heart rate is the fastest your heart can beat when you are exercising as hard as you can. Maximum heart rate changes as you get older.
    • 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.

What else should you know about the test?

  • No electricity passes through your body during the test. There is no danger of getting an electrical shock.
  • During the test, tell your doctor if:
    • You have chest pain.
    • You are very short of breath.
    • You are light-headed.
    • You have other symptoms.

How long does the test take?

  • The test usually takes 15 to 30 minutes.

What happens 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.

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 chest pain that does not go away with rest or is 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 call line if you have any problems.

Follow-up care is a key part of your treatment and safety. Be sure to make and go to all appointments, and call your doctor or nurse call line if you are having problems. It's also a good idea to keep a list of the medicines you take. Ask your doctor when you can expect to have your test results.

Where can you learn more?

Go to https://www.healthwise.net/patientEd

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