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Bicuspid Aortic Valve


Lee B. Beerman

, MD, Childrens Hospital of Pittsburgh of UPMC, University of Pittsburgh School of Medicine

Last full review/revision Dec 2020| Content last modified Dec 2020
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Bicuspid aortic valve is the presence of only two (rather than the normal three) valve cusps.

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


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.


  • 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.


  • 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.

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