Aortic insufficiency is a heart valve disease in which the aortic valve weakens or balloons, preventing the valve from closing tightly. This leads to backward flow of blood from the aorta (the largest blood vessel) into the left ventricle (the left lower chamber of the heart).
Aortic insufficiency can result from any condition that weakens the aortic valve. The condition causes dilation (widening) of the left lower chamber of the heart, which continues to get worse with time. As this area of the heart becomes dilated, it is less able to pump blood to the rest of the aorta. The heart tries to make up for the problem by sending out larger amounts of blood with each heart contraction. This leads to a strong and forceful pulse (bounding pulse).
