Experimental evaluation and early clinical results of a new low-profile bileaflet aortic valve.

We performed an experimental and clinical evaluation of a new low-profile bileaflet aortic valve (Regent, St. Jude Medical Inc., St. Paul, MN, U.S.A.). Common valve sizes were experimentally tested for leakage volume, pressure drop, and transvalvular hemodynamics using a pulse duplicator. Thirty patients (mean age 60 +/- 7 years, predominant valve stenosis n = 25) received the Regent prosthesis for initial clinical evaluation. In vitro evaluation revealed equivalent leakage volumes, larger performance indices (0.552 versus 0.513), and lower pressure drops in comparison to SJM hemodynamic plus valve controls. Clinically, 21 mm (n = 9), 23 mm (n = 12), and 25 mm (n = 9) valves were implanted with no significant perioperative complications. Echocardiography revealed low transvalvular flow velocities (2.2 +/- 0.4 m/s) and low pressure gradients (20 +/- 6 mm Hg) postoperatively and at 6 months follow-up. In vitro testing and early clinical results are promising; however, long-term performance has to be proven.