Wha is a aortic stenosis?

Tight valve: Aortic stenosis is tightening of the aortic valve. There are more rare forms of sub-valvular (below the valve) and supra-valvular (above the valve) as well.

Tightening: Aortic stenosis is a decrease in the size of the area of the aortic valve. This can be congenital (born with it), infectious, acquired (due to atherosclerosis). Treatment is medical (if possible), interventional, or surgical.