[Quadricuspid aortic valve: report of a case associated with severe aortic regurgitation].

A case of quadricuspid aortic valve is reported. A 53-year-old man was admitted to our hospital for exertional dyspnea. He had a grade 3/6 to & fro murmur along the left sternal border. Aortogram showed grade 3 aortic regurgitation. The aortic valve consisted of two equal larger cusps and two equal smaller cusps, and a supernumerary cusp located between the right and noncoronary cusps. Aortic valve replacement was performed successfully and his post operative course was uneventful. On histological examination, the resected cusps showed fibrotic thickening and no sign of previous inflammatory disease. Quadricuspid aortic valve has been extremely rare. 27 Japanese cases of quadricuspid aortic valve which were corrected surgically are reviewed.