Smoking and HEart Disease

Q: Most people know about the dangers of smoking. But how exactly does smoking affect the heart?

A: Smoking increases blood pressure, decreases exercise tolerance, decreases HDL (“good” cholesterol), and increases the tendency for blood to clot. It facilitates the process of atherosclerosis, the buildup of fatty substances in the arteries supplying the heart muscle, brain, and other parts of the body. Smoking also increases the risk of recurrent coronary heart disease after bypass surgery, and increases the risk of aortic aneurysm and peripheral arterial disease.

Nicotine inhaled in smoke decreases oxygen to the heart, causes blood vessels to constrict, increases heart rate, and damages cells that line coronary arteries. Second-hand smoke also increases the risk of heart disease.

Jennifer H. Mieres, M.D., is director of nuclear cardiology and associate professor of clinical medicine at New York University. She’s also a spokesperson for the American Heart Association.