(A.) 4D flow MRI visualization of peak systolic flow using 3D pathlines (color-coded for velocity gradient) demonstrated asymmetric helical flow in RL- and RNC- BAV patients compared to more uniformly distributed flow in trileaflet controls. (B.) Locations of the top 15% of systolic velocities (mapped across a 2D analysis plane in the mid-ascending aorta) were centrally distributed in controls and concentrated towards the outer aortic wall in BAV patients. RNC-BAV subjects showed more variation in distribution compared to RL-BAV, whose flow profile was more consistently directed towards the right-anterior wall.