Anatomic guided crossing of a stenotic aortic valve under fluoroscopy: "right cusp rule, part III".

The retrograde crossing of a severely stenotic aortic valve (AV) is a crucial step in the course of the transfemoral transcatheter aortic valve replacement (TAVR) procedure. Crossing the valve can be time-consuming, and it can substantially increase the risk of cerebral embolism. Omran et al. (1) reported a 22% rate of focal diffusion-imaging abnormalities onmagnetic resonance imaging in patients undergoing retrograde catheterization of the aortic valve; 3% of these patients presented with clinically apparent neurological deficits.