The aortic valve is located between the left ventricle (the heart's main pumping chamber) and the aorta (the main artery that carries blood from the heart to the body). Each time the heart pumps, the aortic valve opens and creates a one-way gate through which blood flows out to the body. In aortic valve regurgitation (also called insufficiency) the valve doesn’t close properly after each heartbeat. This allows blood that was just pumped out to leak back into the left ventricle.
Aortic valve regurgitation can be caused by any condition that enlarges the aorta (such as Marfan’s syndrome or rheumatoid arthritis), valve infection (endocarditis), or any disease that affects the valve leaflets (tissue flaps that close and open over the valve) or inherited conditions (such as a valve with one or two leaflets instead of the normal three).