Acute severe aortic insufficiency during cardiopulmonary bypass in a bicuspid aortic valve with unrecognized annular displacement and fibrous strands: a case report.

Intra-operative acute massive aortic regurgitation may be caused by a morphologically abnormal aortic leaflet and root complex in patients with a BAV. The dilated aortic root, asymmetrical leaflet, and abnormal aortic leaflet insertion, with thick septal myocardium of the coronary aortic sinus, might have caused unstable leaflet co-aptation, leading to deformation of the aortic leaflets influenced by the change in myocardial tone and intra-operative change in the sinotubular junction. Familiarity with the classification of congenital BAV, and the anatomy of the normal and abnormal aortic root complex, is important.