Stress Tests

Stress tests show how well your heart works when it's pumping hard. Some heart diseases are easier to find when your heart is working its hardest to pump blood through your body. So stress tests check your heart while you exercise on a treadmill or stationary bicycle.

If you're not able to exercise, medicine can be used to make your heart work harder , as if you were exercising. There are different types of stress tests. They all check: Blood flow in your heart; Your blood pressure; The rate and rhythm of your heartbeat; The strength of the electrical signals that control your heartbeat; Some stress tests also take pictures of your heart at rest and when it's working hard.

The pictures provide more detail about how your heart is working.

Why this test is done

You may need a stress test if you have symptoms that could be from a heart condition. Symptoms may include:

• Chest pain or discomfort without a known cause
• Shortness of breath
• Irregular or rapid heartbeat that may feel like a fluttering in your chest
• Feeling dizzy or lightheaded

You may also need a stress test to check your heart health if you:

• Have a heart condition with new or worsening symptoms.
• Are going to have surgery. Your health care provider may want to see if your heart is strong enough for the operation.
• Are being treated for heart disease. The test can show how much treatment is helping, including heart surgery.
• Have a high risk for heart disease. Your risk may be higher than normal if you have a family history of heart disease and/or certain conditions, such as diabetes, that are linked to heart disease.
• Plan to start an exercise program. If you have a heart condition or a high risk for a heart condition, a stress test can show what level of exercise is safe for you. (Always talk with your provider before starting any strenuous, new exercise.)

How to prepare

Wear comfortable shoes and clothing for exercise. Your provider will tell you what else to do before a stress test. You'll usually need to fast (not eat or drink) and stop smoking for at least a few hours before the test.

You may need to avoid drinks with caffeine, such as coffee, tea, and colas, for a longer period of time.

If you take medicines or supplements, ask your provider if you should take them as usual. Don't stop taking any medicine unless your provider tells you to. If your test uses MRI, tell your provider about any metal you have in your body.

An MRI can heat certain metal and cause burns.

Sample type

Blood

Other names for this test

exercise stress test, treadmill test, stress EKG, stress ECG, exercise tolerance test, exercise EKG, stress echocardiogram, nuclear stress test, thallium stress test, sestamibi stress test, cardiac MRI stress test, myocardial perfusion imaging test, cardiac single photon emission computed tomography (SPECT), stress perfusion test