Quadricuspid aortic valve: a report on a 10-year case series and literature review.

Quadricuspid aortic valve is rare, with an estimated incidence of 0.008% to 1.46%. Most cases are encountered incidentally during aortic valve surgery or autopsy. The condition frequently progresses to aortic regurgitation, which can manifest in adulthood and may require surgical treatment. This anomaly may sometimes be associated with other malformations, the most common being coronary artery anomalies. We performed a retrospective chart review of patients diagnosed with quadricuspid aortic valve between January 2002 and July 2012 and report here on cases treated surgically. We encountered three cases of quadricuspid aortic valve among 627 patients undergoing aortic valve surgery at our institution (an incidence of 0.48%). All three had aortic regurgitation and two were free of cardiac anomaly; the other had ascending aortic aneurysm and coronary malformation. According to Hurwitz's classification, two of the valves were of type b and one of type d. Under Nakamura's classification, meanwhile, two of the valves were type II and the other type III. All patients underwent successful aortic valve replacement and had uneventful postoperative courses.