Aortic Diseases & Disorders
Bicuspid Valve Disease
Bicuspid aortic valve
Bicuspid aortic valve (BAV) is the most common birth defect affecting the heart and is present in 1-2% of the population. Bicuspid aortic valve is much more common in males than females.
There are three main forms of bicuspid aortic valve disease, as classified by Hans Sievers, MD in 2007. These types vary according to the number of 'cusps' and 'raphes' (arrow-shaped formations of tissue, also called 'false commissures'), and their position and functional status. 'Cusps' refer to the tips in the valve. 'Raphes' refer to the fused areas where undeveloped cusps form a malformed commissure, and appear like ridges with elastic fibers.
Types of bicuspid aortic valve:
Type 0: no raphes (so-called 'purely' BAV)
Type 1: 1 raphe
Type 2: 2 raphes
Bicuspid Aortic Valve and Risk of Aneurysm
In a bicuspid aortic valve, the valve leaflets do not open as fully they should. This causes turbulence as the blood flows through the valve. It creates areas around the valve where blood stagnates a bit, and other areas around the valve where the blood is under high pressure. This imbalance puts an abnormal amount of pressure on the valve, which sets the stage for damage to occur. Once damage occurs, the areas of stagnation or pooling will allow calcium to deposit on the valve. This will result in thickening and incomplete opening. This process continues until the valve is destroyed. It is important to note that not everyone with a bicuspid valve will have this problem, but that there is an increased likelihoodof calcium deposits forming on the leaflets. It is important to note that the risk of developing bicuspid aortic valve has a genetic basis. Anyone who has a relative who had a bicuspid valve, an aneurysm, or a dissection should have an echocardiogram to assess the structure and function of their aortic valve.
Read about bicuspid aortic valve replacement.
