Bicuspid aortic valve is the most common congenital cardiovascular abnormality. It is present in 0.5 to 2 % of live births (1 General references Bicuspid aortic valve is the presence of only two (rather than the normal three) valve cusps. Bicuspid aortic valve is the most common congenital cardiovascular abnormality. It is present in... read more ).
Patients with bicuspid aortic valve are predisposed to developing infective endocarditis Prevention Infective endocarditis is infection of the endocardium, usually with bacteria (commonly, streptococci or staphylococci) or fungi. It may cause fever, heart murmurs, petechiae, anemia, embolic... read more 
, aortic regurgitation Aortic Regurgitation Aortic regurgitation (AR) is incompetency of the aortic valve causing backflow from the aorta into the left ventricle during diastole. Causes include valvular degeneration and aortic root dilation... read more 
, and/or aortic stenosis Aortic Stenosis Aortic stenosis (AS) is narrowing of the aortic valve, obstructing blood flow from the left ventricle to the ascending aorta during systole. Causes include a congenital bicuspid valve, idiopathic... read more 
. Bicuspid aortic valve can also be associated with dilation of the aortic root or ascending aorta and coarctation of the aorta Coarctation of the Aorta Coarctation of the aorta is a localized narrowing of the aortic lumen that results in upper-extremity hypertension, left ventricular hypertrophy, and malperfusion of the abdominal organs and... read more .
There is a genetic predilection for bicuspid aortic valves with a 9% reported family prevalence, so first-degree relatives of patients with a bicuspid aortic valve should undergo screening echocardiography. Recognition of a bicuspid valve, even in a patient who has normal valve function, is important for purposes of follow-up because of the association of bicuspid valves with progressive aortic root or ascending aortic dilation and aneurysm formation. The reported prevalence of this complication varies widely in different studies, but, in general, dilatation will occur in up to 56% of those aged < 30 years (2 General references Bicuspid aortic valve is the presence of only two (rather than the normal three) valve cusps. Bicuspid aortic valve is the most common congenital cardiovascular abnormality. It is present in... read more ).
General references
1. Freeze SL, Landis BJ, Ware SM, Helm BM: Bicuspid aortic valve: a review with recommendations for genetic counseling. J Genet Couns 25(6):1171–1178, 2016.
2. Tadros TM, Klein MD, Shapira OM: Ascending aortic dilatation associated with bicuspid aortic valve: pathophysiology, molecular biology, and clinical implications. Circulation 119(6):880–890, 2009. doi: 10.1161/CIRCULATIONAHA.108.795401
Symptoms
Children with bicuspid aortic valve may be asymptomatic if there is little or no valve dysfunction. Symptoms depend on the type of complication and can include fever in infective endocarditis or dyspnea, fatigue, syncope, palpitations, and exercise intolerance due to valvular regurgitation or stenosis. Examination reveals an early systolic click, a systolic ejection murmur and, if aortic regurgitation is present, a diastolic decrescendo murmur.
Diagnosis
Echocardiography
Diagnosis is by physical examination findings and echocardiography. Echocardiography shows the characteristic finding of fusion of two of the three aortic valve leaflets. Fusion of the right coronary and left coronary leaflets is the most common morphology. Children with fusion of the right coronary and noncoronary leaflets are more likely to have progression of valve dysfunction and to require intervention during childhood.
Treatment
Balloon dilation or surgical repair
Treatment of bicuspid aortic valve is indicated if severe valve dysfunction develops and if symptoms occur. Treatment consists of balloon dilation or surgical repair of stenotic valves. Regurgitant valves are treated with surgery.
More Information
The following is an English-language resource that may be useful. Please note that The Manual is not responsible for the content of this resource.
American Heart Association: Common Heart Defects: Provides overview of common congenital heart defects for parents and caregivers
