Isolated quadricuspid aortic valve

Isolated quadricuspid aortic valve (QAV) is a very rare cardiac anomaly, with an estimated incidence of 0.031 to 0.043% among all congenital heart diseases (1). Although association with other anomalies has been reported, QAV very often presents as an isolated congenital anomaly (2). According to Hurwitz and Roberts’ classification, QAV is divided into 7 types (A to G) with respect to the size of the AV cusps (Table 1). Types A and B are the more common types. Aortic regurgitation as a usual complication of QAV occurs in type B with high eventuality because of its specific anatomy and unbalanced stress on the cusps.