What does it mean if my angiogram shows that I have a stenosis?

A stenosis is a narrowed area inside a blood vessel. If you have coronary artery disease, the outer diameter of the affected artery stays about the same size as a normal artery. The inner diameter is narrower than a normal artery, however, as the result of deposits of cholesterol, fat, calcium and blood cells. These deposits are called plaque.

Your cardiologist will determine the percent stenosis by comparing the inner diameter of your artery at the narrow point with a normal part of the artery nearby. A 50 percent stenosis means that plaque build-up is constricting the inner diameter of the artery by half.

Your cardiologist will use the percent stenosis to help determine the best treatment. Usually, a 70 percent stenosis is considered serious enough to warrant treatment with angioplasty, which widens the narrowed portion of the artery by inflation of a tiny balloon, and/or stenting, in which a small metal tube is positioned in the artery to prop it open. This is not a hard-and-fast cutoff, however. For example, patients with 60 percent stenosis may have angioplasty and stenting if they are considered high-risk for other reasons or have been having a lot of worrisome symptoms.

 For some patients bypass surgery, which re-routes blood flow around the narrowed area inside the blood vessel, is the best treatment.

If your angiogram reveals a stenosis that is not considered serious, your cardiologist may recommend preventive medical therapy to control your cholesterol levels and blood pressure, and minimize the chance of blood clots clumping together on the cholesterol plaque.