Standard medical guidelines state that routine stress tests are inappropriate within two years of angioplasty and five years of bypass surgery. They suggest patients do not need to have a stress test unless they have chest pains.
However, in a study of more than 28,000 patients who had angioplasty or bypass surgery, researchers found that 59 percent had at least one stress test within two years of the procedure.
Performing cardiac stress tests on symptom-free patients can lead to unnecessary invasive procedures.
The findings are reported in the Journal of the American College of Cardiology.