A heart attack in progress is a medical emergency. The leading way to stop it is with artery-opening angioplasty. But many angioplasties are done for reasons other than heart attack. Some are performed to ease chest pain that appears with physical activity or stress. This is the chest pain known as stable angina. Sometimes the prospective patient has no symptoms at all — just test results that indicate one or more clogged arteries. Cardiologists continuously debate when it’s appropriate to do non-emergency angioplasty. Two studies in JAMA Internal Medicine add some provocative new information: that incomplete or even misleading advice from doctors contributes to unnecessary angioplasties. And that’s a problem because angioplasty can harm as well as help.