Aortic Stenosis Aortic stenosis is narrowing of the aortic valve due to calcification of the valve leaflets or valvular damage. Aortic stenosis commonly occurs at an early age in patients with congenital bicuspid aortic valves. The most common cause of aortic stenosis is calcification of the valve leaflets with age, with the prevalence of aortic stenosis increasing rapidly beginning in the 7th decade. Aortic stenosis can also result from rheumatic fever. Though rheumatic fever is most strongly a