Aortic stenosis
Causes include being born with a bicuspid aortic valve, and rheumatic fever; a normal valve may also harden over the decades due to calcification. A bicuspid aortic valve affects about one to two percent of the population. As of 2014 rheumatic heart disease mostly occurs in the developing world. Risk factors are similar to those of coronary artery disease and include smoking, high blood pressure, high cholesterol, diabetes, and being male. The aortic valve usually has three leaflets and is located between the left ventricle of the heart and the aorta. AS typically results in a heart murmur. Its severity can be divided into mild, moderate, severe, and very severe, distinguishable by ultrasound scan of the heart.
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