Doppler-derived gradients may overestimate total pressure loss in degenerative and prosthetic aortic valve stenosis (AS), due to unaccounted pressure recovery distal to the orifice. However, in congenitally bicuspid valves, jet eccentricity may result in higher anatomic-to-effective orifice contraction ratio resulting in an increased pressure loss at the valve and a reduced pressure recovery distal to the orifice leading to greater functional severity. The objective of our study was to determine the impact of local geometry on the total versus Doppler derived pressure loss and therefore the assessed severity of the stenosis in bicuspid valves. Methods and Results: Based on clinically obtained measurements, 2 and 3-dimensional computer simulations were created with various local geometries by altering the diameters of the left ventricular outflow tract (LVOT; 1.8-3.0cm), orifice (OD; 0.8-1.6cm), and aortic root diameter (AR; 3.0-5.4cm). Jet eccentricity was altered in the models from 0 to 25 degrees. Simulations were performed under steady flow conditions. Axisymmetric simulations indicate that the overall differences in pressure recovery were minor for variations in LVOT diameter (less than 3%). However, both OD and AR had a significant impact on pressure recovery (6-20%), with greatest recovery the larger OD and the smaller the AR. In addition, 3D data illustrate a greater pressure loss for eccentric jets with the same orifice area, thus increasing functional severity.