A stress test, also called an exercise stress test, shows how your heart works during physical activity. Because exercise makes your heart pump harder and faster, an exercise stress test can reveal problems with blood flow within your heart.
A stress test usually involves walking on a treadmill or riding a stationary bike your heart rhythm, blood pressure and breathing are monitored. Or you'll receive a drug that mimics the effects of exercise.
Your doctor may recommend a stress test if you have signs or symptoms of coronary artery disease or an irregular heart rhythm (arrhythmia). The test may also guide treatment decisions, measure the effectiveness of treatment or determine the severity if you've already been diagnosed with a heart condition.
Your doctor may recommend a stress test to:
• Diagnose coronary artery disease. Your coronary arteries are the major blood vessels that supply your heart with blood, oxygen and nutrients. Coronary artery disease develops when these arteries become damaged or diseased — usually due to a buildup of deposits containing cholesterol and other substances (plaques).
• Diagnose heart rhythm problems (arrhythmias). Heart arrhythmias occur when the electrical impulses that coordinate your heart rhythm don't function properly, causing your heart to beat too fast, too slowly or irregularly.
• Guide treatment of heart disorders. If you've already been diagnosed with a heart condition, an exercise stress test can help your doctor find out how well treatment is working. It may also be used to help establish the treatment plan for you by showing how much exercise your heart can handle.
Your doctor may use a stress test to help determine the timing of cardiac surgery, such as valve replacement. In some people with heart failure, stress test results may help the doctor determine whether you need a heart transplant or other advanced therapies.