title: Another cause of severe aortic regurgitation: congenital quadricuspid aortic valve.
authors.forename: Ibrahim
authors.initials: I
authors.lastname: Akin
authors.forename: Hüseyin
authors.initials: H
authors.lastname: Ince
authors.forename: Christoph A
authors.initials: CA
authors.lastname: Nienaber
mesh_terms: D000328:Adult; D001021:Aortic Valve / Q000002:abnormalities* / Q000000981:diagnostic imaging; D001022:Aortic Valve Insufficiency / Q000209:etiology*; D017548:Echocardiography, Transesophageal; D005260:Female; D006801:Humans; D011859:Radiography