Schubert and colleagues developed a novel trileaflet mechanical heart valve prosthesis. They compared this device with a conventional mechanical bileaflet heart valve in vitro, evaluating hemodynamic parameters and thrombogenicity. The trileaflet valve had a larger effective orifice area and smaller pressure gradient than the bileaflet one. There were fewer clotting deposits on the trileaflet valve, and the authors pointed to the off-wall systolic position of the hinges in the new valve as a major advantage.