Fig. (1) A) Photo of a mechanical left heart model showing a transparent elastic left ventricle viewed from the apex, the mechanical heart valve (MHV) and the aortic root (AR). Imaging planes are denoted by white lines and correspond to: 1 (90°), 2 (45°), 3 (0°), 4 (-45°). B) Placement of the bileaflet mechanical heart valve in the removable atrioventricular module in 0, 45, and 90 degree angular positions (viewed from the left atrium).