Ask the doctor

How risky is bypass surgery?

Q. Like President Clinton, I have four very clogged coronary arteries (70% to 90% closed). My cardiologist pushed for bypass surgery but I resisted. A year later, the blockages have decreased somewhat. I haven't had much luck finding out about complications from and survival after bypass surgery. Can you help?

A. You would think that an expert from Harvard should be able to give you a simple answer to a simple question: What are the chances something bad will happen to me if I do or don't have bypass surgery? But I can't. Many factors determine one's odds of having complications during surgery. The number of blockages and the severity of the narrowings are less important than you might think. One key issue is whether your heart muscle has been damaged by prior heart attacks, and how severe any damage is. If your left ventricle has been weakened, the chances of having a problem during or soon after surgery goes up. Diabetes, kidney problems, and advanced age also increase your risk.