Exercise tests are performed for varied reasons, such as evaluating fitness, assessing heart rate and blood pressure responses to stress, investigating symptoms such as chest discomfort or breathlessness, and assisting in diagnosis of conditions such as blockages in the coronary arteries.
Because many individuals with heart conditions have exertional symptoms, an exercise test can reveal abnormalities and electrocardiographic changes when these symptoms occur that are not apparent at rest. However, exercise tests are unable to detect early plaque in a coronary artery that is not yet blocking blood flow, and thus their accuracy in detecting heart disease remains imperfect. Despite these limitations, exercise testing may be useful to evaluate your overall heart health in specific situations. One very important piece of information is simply how long and to what level of work you can exercise. Your fitness and heart health can be estimated by the duration and the highest treadmill speed and incline you can achieve. In general, people who have higher fitness levels are at lower risk for a heart attack.
An exercise test is usually conducted on clinically stable patients capable of performing physical activity. Common reasons not to perform an exercise test include acute illness, uncontrolled disease (eg, elevated blood pressure), or certain electrocardiographic abnormalities. Routine or annual exercise testing for patients without symptoms is generally not recommended.
An exercise test is usually performed on a treadmill or a stationary cycle. Electrocardiographic and blood pressure readings are taken regularly to monitor the heart’s response. The workload gradually increases as the test progresses, and the test is stopped when you are too tired to continue or when there are specific changes in heart rate or blood pressure. In some situations, imaging with an echocardiogram (ultrasonography) or nuclear tracers is part of the exercise test to enhance the diagnosis of underlying heart disease. The accuracy of the test in detecting heart disease depends on adequately stressing the heart. For people who are unable to exercise fully (because of age, other medical conditions, or infirmity), intravenous medications can be given to simulate the effects of exercise. However, whenever possible, exercise is greatly preferred.
Exercise tests are generally safe (<4 potentially serious events occur every 1000 tests). The safety of an exercise test depends primarily on the patient’s clinical history and the experience of those who perform the test. An abnormal test, depending on symptoms and electrocardiographic changes, may suggest blocked coronary arteries or impaired heart function. Many times an exercise test is performed to determine who would benefit from coronary angiography in which catheters are inserted in the heart to obtain images of the coronary arteries. Exercise test results also help physicians determine whether specific heart medications will be helpful. They can also help your physician understand why you may be having symptoms, whether these symptoms are caused by a heart condition, and how to best treat you.
Learning more about how your heart is working under stress may also provide reassurance and the opportunity to discuss how to improve your fitness and lifestyle.
Published Online: November 2, 2016. doi:10.1001/jamacardio.2016.3761
Conflict of Interest Disclosures: All authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest and none were reported.
Sources: Fletcher GF, Ades PA, Kligfield P, et al; American Heart Association Exercise, Cardiac Rehabilitation, and Prevention Committee of the Council on Clinical Cardiology, Council on Nutrition, Physical Activity and Metabolism, Council of Cardiovascular and Stroke Nursing, and Council on Epidemiology and Prevention. Exercise standards for testing and training: a scientific statement for healthcare professions from the American Heart Association. Circulation 2013;128(8):873-934.
Myers J, Forman DE, Balady GJ, et al; American Heart Association Subcommittee on Exercise, Cardiac Rehabilitation, and Prevention Committee of the Council on Clinical Cardiology, Council on Lifestyle and Cardiometabolic Health, Council on Epidemiology and Prevention, and Council of Cardiovascular and Stroke Nursing. Supervision of exercise testing by nonphysicians: a scientific statement from the American Heart Association. Circulation 2014;130(12):1014-1027.
Franklin BA, Berra K, Lavie CJ. Should I Have an Exercise Stress Test?. JAMA Cardiol. 2016;1(9):1084. doi:10.1001/jamacardio.2016.3761