Bicuspid Aortic Valve
Bicuspid Aortic Valve Complications
With the degeneration of aging valves, sclerosis and calcification can occur, with results similar to those in atherosclerotic coronary arteries. The bicuspid valve may also be completely functional, producing no regurgitant flow. However, redundancy and prolapse of cusp tissue can result to valve regurgitation. Although bicuspid aortic valve is a common abnormality, complications may come about in as many as one third of patients over their lifetimes. This disorder, therefore, requires close attention and medical follow-up.
Bicuspid Aortic Valve Definition
A bicuspid aortic valve is a heart valve possessing two cusps that are situated between the left ventrical and the aorta. A congenitally bicuspid aortic valve has 2 working leaflets. Most people have 2 complete commissures. An approximated half of cases have a low raphe. Excluded are stenotic or partially fused valves caused by inflammatory processes, such as rheumatic fever.
Bicuspid Aortic Valve Historical Background
Patients with bicuspid aortic valves may have no symptoms at all. About 30% of individuals with a bicuspid aortic valve develop complications from the condition. If symptoms are displayed, they relate to the development of aortic stenosis, aortic insufficiency, or both. Occasionally, a congenitally bicuspid aortic valve may be the result of critical aortic stenosis, with symptoms of severe congestive heart failure developing in early on in infancy. This critical form of stenosis is more often associated with a unicommissural valve. In patients in whom a bicuspid aortic valve is seen in association with other types of left heart obstruction (coarctation or interrupted aortic arch), the bicuspid valve generally works well, and symptoms are usually caused by the associated disorder. Although most cases of bicuspid aortic valve are sporadic, familial clusters have been identified, with incidence reaching as high as 10-17% in first-degree relatives. Increasing evidence suggests an autosomal-dominant inheritance pattern with variable penetrance, encompassing the entire range of left heart obstruction (hypoplastic left heart syndrome, aortic stenosis, coarctation of the aorta).
Bicuspid Aortic Valve Prevalence
About 1-2% of the population have bicuspid aortic valves, although the condition is nearly twice as common in male patients. Incidence does not appear to be dependent on race or geography Bicuspid aortic valve has been found to be a condition that is inheritable, with a demonstrated association with Notch 1. Familial clustering as well as isolated valve defects has also been documented. The incidence of bicuspid aortic valve can be as high as 10% in families that have a history with the valve problem. Other congential heart defects are connected with bicuspid aortic valve at various frequencies.