Single raphe bicuspid aortic valve Bicuspid aortic valve with right-left cusp fusion 2017-06-10T11:48:42Z A type of bicuspid aortic valve (BAV) characterized by a single raphe between the right and left cusps (RL fusion pattern). This results in two leaflefts with an anterior-posterior leaflet orientation (also called the typical pattern). There is thus one completely developed noncoronary cusp, two completely developed commissures, and one raphe between the underdeveloped left and right coronary cusps extending to the corresponding malformed commissure.