Every year, thousands of Americans have an exercise stress test to find out how well their hearts can handle a workload. Should you be one of them? Johns Hopkins offers advice.
Most people who have an exercise stress test either have diagnosed coronary heart disease or symptoms that suggest heart disease, such as chest pain or shortness of breath. And if you are healthy, have no heart disease, symptoms, and have no risk factors for heart disease, you probably don’t need a stress test. But the answer to the question gets murkier if you’re symptom free but have risk factors such as older age, high blood pressure, elevated LDL cholesterol levels, or cigarette smoking.
The American Heart Association (AHA) offers some guidance. According to a scientific statement, the organization concluded there was insufficient evidence to recommend routine use of exercise stress testing in people with no symptoms of heart disease.
What’s more, they noted that the test could be detrimental for symptom-free individuals, because a false-positive result is common -- especially in symptom-free women.
But studies coming on the heels of the AHA statement are helping doctors better understand which symptom-free people may benefit most from an exercise stress test and how to perform the test to get the most meaningful results. One of these studies was led by Roger S. Blumenthal, M.D., coauthor of the 2008 Johns Hopkins Heart Attack Prevention White Paper. The study included more than 6,000 men and women without symptoms of heart disease, who were at low to moderate risk for a heart attack, according to their Framingham risk score.
At the beginning of the study, the participants underwent an exercise stress test -- but it was not the conventional test. Instead of just looking for changes in the electrical activity of the heart, the researchers also measured exercise capacity (how long the participant could exercise) and heart rate recovery (how quickly the participant’s heartbeat returned to normal after exercise).
Twenty years later, 246 of the participants had died of cardiovascular disease (a heart attack or stroke). What was striking was that 90% of these deaths occurred in people with below-average results on the exercise capacity and heart rate recovery components of the exercise stress test. Based on the results, the researchers estimated that about half of the men and women at moderate risk according to their Framingham risk score were really at high risk for a heart attack; the same was true for about half of the women deemed low risk by their Framingham score.
Bottom line advice -- Until more research comes in on the value of exercise testing for people without symptoms of CHD, the decision to have an exercise stress test remains very much an individual one.
