Coronary angiogram (right anterior oblique view) showing stages of stenosis in the anterior interventricular arteryWhat are the risk factors for aortic stenosis? What causes calcium buildup in patients with this condition?
—MARY LANDSBERGER, ARNP-C, Brandon, Fla. 

Risk factors for aortic stenosis include a bicuspid aortic valve, radiation, rheumatic fever, atherosclerosis, and untreated strep throat. In rare instances, aortic stenosis is associated with use of certain medications (e.g., ergotamine). Hypercholesterolemia contributes to degenerative changes of the aortic valve. Aortic valve stenosis may also be caused by an age-related buildup of calcium deposits. As blood repeatedly flows over the aortic valve, calcium deposits can accumulate on and stiffen the valve’s leaflets (more often with bicuspid aortic valves). This stiffening, which narrows the valve, is most common in people older than age 60 years.
—Debra Kleinschmidt, PhD, PA
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