AS and AR are short forms of aortic stenosis and aortic regurgitation. The aortic valve of the heart either gets stenosed (the orifice becomes narrow) or regurgitates (there is a leak in the valve). So AS and AR are the disease process of aortic valve of the heart. The treatment for this depends on the severity of AS & AR. When it gets worse, then the aortic valve replacement is the treatment of choice. In milder form of AS & AR, medical treatment usually suffices.
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