Why an EKG is not a good screening test for heart disease
Our recent Ratings of screening tests for heart disease have attracted some praise, such as from health-care blogger Gary Schwitzer, but some criticism, too. Most of the latter has focused on the negative Rating we gave to an electrocardiogram (EKG) as a screening test for heart disease. Here’s when we think an EKG is appropriate, and why we think it’s not a great way to screen healthy people for heart disease.
An EKG, which measures electrical activity in the heart, is clearly warranted for anyone who has symptoms of heart disease, such as chest pain. In fact, we say it’s usually the first test such people should have, typically combined with an exercise stress test. We also say it might make sense for certain other people, such as middle-aged people who are just starting to exercise, and possibly as a baseline in people 50 or older.
But that’s not the only time people get EKGs. Many doctors include the test as part of a routine check up. In our recent survey of heart tests, half of the participantsall of whom had no history or symptoms of heart diseasesaid they had had an EKG as a part of routine exam. And one healthy, physically active 44 year-old woman I work with told me that she’s had an EKG every year since she was in college. As Steven Nissen, M.D., chairman of cardiovascular medicine at the Cleveland Clinic in Ohio told us, “That’s generally a bad idea,” because the test is “not as accurate in low-risk people and can trigger unnecessary and expensive follow-up.”
For example, an abnormal finding on an EKGwhich is commonmight lead to CT angiography, which can expose you to a significant dose of radiation. That might lead to an angiogram, which has a 1 to 2 percent chance of a significant side effect. And that might detect a mildly blocked coronary artery. And while research suggests such blockages typically don’t need to be treated with angioplasty, many cardiologists who see this kind of blockage will feel compelled to treat it anyway.
That’s why weas well as the U.S. Preventive Service Task Force, the American Academy of Family Physicians, the American College of Cardiology, and the American Heart Associationdon’t recommend routine EKGs as a way to screen for heart disease in healthy people.
Use our calculator to estimate your risk of having a heart attack or stroke in the next 10 years.