A diseased or damaged valve can affect the flow of blood in two ways: This can put extra strain on your heart, making it pump harder to force the blood past the narrowing. If the valve does not close properly, it will allow blood to leak backwards. This is called valve incompetence or regurgitation or a leaky valve.

Many healthy people have one or more valves that are slightly leaky. If the heart valve leak is severe, it may impair the forward flow of blood. This can cause symptoms of congestive heart failure, which include: Shortness of breath, especially with exertion or when lying flat.

A defective valve has only two leaflets, so it's called a bicuspid valve. A recent study found that aortic valve replacement procedural treatment has a 94 percent five-year survival rate.