Stress Test

The National Heart, Lung, and Blood Institute (NHLBI) says some heart problems are easier to diagnose when your heart is working harder and beating faster than when it's at rest. During stress testing, you exercise (or are given medicine if you are unable to exercise) to make your heart work harder and beat faster while heart tests are performed. (Read about "Cardiovascular Tests")

During exercise stress testing, you will be hooked up to a variety of monitors so that your blood pressure (Read about "Hypertension: High Blood Pressure") and EKG readings (Read about "EKG - Electrocardiogram") can be monitored before, during, and/or after the procedure. While being monitored, you will walk or run on a treadmill or pedal a bicycle.

If you are unable to exercise, a medicine can be injected through an intravenous line (IV) into your bloodstream to make your heart work harder and beat faster, as if you are exercising on a treadmill or bicycle.

Other heart stress tests, using nuclear heart scanning or echocardiography, also can be done at the same time as a regular stress test. These would be ordered if your doctor needs more information than the regular exercise stress test can provide about how well your heart is working.

• During a nuclear stress test (also called nuclear heart scanning or a thallium stress test), radioactive tracer is injected into your bloodstream after you reach your maximum level of exercise during the regular stress test. You then lie down on a special table under a camera that shows the flow of blood through your heart and arteries by tracing the nuclear material in your blood. This picture of your heart when it is "stressed" is then compared with a picture taken of your heart at its resting rate. (Read about "Nuclear Medicine")
• During an echo stress test, pictures are taken of your heart during exercise and at rest using echocardiography. Echocardiography uses sound waves to show blood flow through the chambers and valves of your heart and to show the strength of your heart muscle. (Read about "Ultrasound Imaging")

A stress test lets the doctor see how your heart responds to exercise, and also what level of exercise is appropriate for you. This test can be used in the diagnosis of heart disease. (Read about "Coronary Heart Disease") It can also be used to help diagnose the cause of problems you may be having such as angina or chest pain. (Read about "Angina") It can help to predict your risk of dangerous heart-related conditions such as a heart attack. (Read about "Heart Attack") If you already have had a heart attack or heart surgery, it can also help your doctor monitor your progress during cardiac rehabilitation. (Read about "Cardiac Rehabilitation")