How does aortic stenosis affect the left ventricle pump?
Symptoms and heart problems in aortic stenosis are related to the degree of narrowing of the aortic valve area. Patients with mild aortic valve narrowing may experience no symptoms. When the narrowing becomes significant (usually greater that 50% reduction in valve area), the pressure in the left ventricle increases and a pressure difference can be measured between the left ventricle and the aorta. An easy way to conceptualize the size issues is to think of a normal aortic valve as being about a “half-dollar” size in diameter, and a significantly narrowed valve to be less than a “dime” in size. To compensate for the increasing resistance at the aortic valve, the muscles of the left ventricle thicken to maintain pump function and cardiac output. This muscle thickening causes a stiffer heart muscle which requires higher pressures in the left atrium and the blood vessels of the lungs to fill the left ventricle. Even though these patients may be able to maintain adequate and normal cardiac
