Bicuspid aortic valve disease is a congenital defect involving the aortic value, which connects the heart and aorta. Instead of having three flaps, known as leaflets, inside the valve, a person with bicuspid aortic valve disease presents with only two leaflets. Without the needed third leaflet, blood may flow back into the heart from the aorta, resulting in strain on heart muscles and the eventual appearance of disease symptoms. Seldom is the disease diagnosed at birth, during childhood, or during adolescence because younger hearts and valves can easily compensate for the deformity. Men are statistically more likely to have the defect than women.
Looking at a diagram of the human heart, the aortic valve can be found inside the end of the aorta, connecting the aorta with the wall of the heart. The aorta is intended to facilitate the flow of blood from the heart to the rest of the body. It is a one-way artery, meaning blood flows in only one direction. Facilitating the one-way flow of blood requires the leaflets in the aortic valve to open completely and close tightly as the heart beats. If a defect is present, such as seen in bicuspid aortic valve disease, the valve may not be able to open or close as widely or as tightly as needed, allowing blood to wash back into the heart.
Although a congenital birth defect, symptoms of bicuspid aortic valve disease typically do not present until later in life, as circulatory system components begin to wear. Owing to aging components and the narrowing and hardening of the aortic valve, the heart strains to continue pumping fresh blood as well as regurgitated blood washed backward from the defective valve. Increasing strain brings on symptoms of the disease, typically during middle age. Resulting symptoms include difficulty breathing or shortness of breath, pains in the chest, and other oxygen deprivation symptoms. In rare cases, bicuspid valve deformities can lead to cardiac arrest and other serious cardiopulmonary problems.
Surgical correction is required in approximately 80 percent of patients with bicuspid aortic valve disease. Replacing the defective valve, and sometimes parts of the aorta, usually resolves issues of blood regurgitation and resulting symptoms. Should aneurysms or tears in the aorta occur as a result of the defective valve, further surgery, synthetic replacements, or cardiac follow up is necessary.
Causes of bicuspid aortic disease are not fully understood. Some research suggests the disease may relate to diseases of connective tissues, since many patients also exhibit signs in other areas of the circulatory system relative to such conditions. Deformities or abnormality in other arteries, high blood pressure, aortic aneurysm and other problems are not uncommon in patients with bicuspid aortic valve disease.