Aortic Stenosis: Causes & Risk Factors

Causes:

-Progressive wear and tear of a bicuspid valve present since birth (congenital defect). It is the most common cause of AS in patients under 65. Over time, excessive wear and tear leads to calcification, scarring, and reduced mobility of the valve leaflets.
-Wear and tear of the aortic valve in the elderly.Protein collagen of the valve leaflets is destroyed, and calcium is deposited on the leaflets. Valve leaflet mobility is reduced by calcification, turbulence across the valve increases, causing scarring, thickening, and stenosis of the valve.
-Scarring of the aortic valve due to rheumatic fever as a child or young adult. Rheumatic fever is a condition resulting from untreated infection by group A streptococcal bacteria. Damage to valve leaflets from rheumatic fever causes increased turbulence across the valve and more damage. The narrowing from rheumatic fever occurs from the fusion (melting together) of the edges (commissures) of the valve leaflets.


Risk Factors:

-3 times more common in men than women
-Age (affects the elderly)