Cardiology Services Education

Cardiac Stress Testing

What Is Stress Testing?

Stress testing gives your doctor information about how your heart works during physical stress. Some heart problems are easier to diagnose when your heart is working hard and beating fast.

During a stress test, you exercise (walk or run on a treadmill or pedal a bicycle) to make your heart work hard and beat fast. Tests are done on your heart while you exercise.

You may have arthritis or another medical problem that prevents you from exercising during a stress test. If so, your doctor may give you medicine to make your heart work hard, as it would during exercise. This is called a pharmacological (FAR-ma-ko-LOJ-i-kal) stress test.

Overview

Doctors usually use stress testing to help diagnose coronary heart disease (CHD), also called coronary artery disease. They also use stress testing to see how severe CHD is in people who have it.

CHD is a condition in which a fatty material called plaque (plak) builds up in the coronary arteries. These arteries supply oxygen-rich blood to your heart.

Plaque narrows the arteries and reduces blood flow to your heart muscle. It also makes it more likely that blood clots will form in your arteries. Blood clots can partly or completely block blood flow. This can lead to chest pain or a heart attack.

You may not have any signs or symptoms of CHD when your heart is at rest. But when your heart has to work harder during exercise, it needs more blood and oxygen. Narrowed arteries can't supply enough blood for your heart to work well. As a result, signs and symptoms of CHD may only occur during exercise.

A stress test can detect the following problems, which may suggest that your heart isn't getting enough blood during exercise.

  • Abnormal changes in your heart rate or blood pressure
  • Symptoms such as shortness of breath or chest pain, which are particularly important if they occur at low levels of exercise
  • Abnormal changes in your heart's rhythm or electrical activity

During a stress test, if you can't exercise for as long as what's considered normal for someone your age, it may be a sign that not enough blood is flowing to your heart. However, other factors besides CHD can prevent you from exercising long enough (for example, lung disease, anemia, or poor general fitness).

A stress test also may be used to assess other problems, such as heart valve disease or heart failure.

Information provided by National Heart Lung and Blood Institute