Rare or unusual causes of chronic, isolated, pure aortic regurgitation

Six patients undergoing aortic valve replacement had rare or unusual causes of isolated, pure aortic regurgitation. Two patients had congenitally bicuspid aortic valves with a false commissure (raphe) displaced to the aortic wall (tethered bicuspid aortic valve), two had floppy aortic valves, one had a congenital quadricuspid valve, and one had radiation-induced valve damage