Hemodynamics and early clinical performance of the St. Jude Medical Regent mechanical aortic valve

Background. The St. Jude Medical Regent valve is the next-generation bileaflet aortic prosthesis, modified from the currently marketed St. Jude Medical mechanical valve to achieve a larger geometric orifice without changing the existing design of the pivot mechanism or blood-contact surface areas. The present study reports the hemodynamic and early clinical results of an ongoing multicenter trial investigating the performance of the Regent valve. Methods. Between July 1998 and July 2001, 361 patients at 17 centers in North America and Europe underwent implantation of a Regent mechanical aortic valve prosthesis. Clinical status was prospectively recorded, and echocardiography with Doppler was performed at discharge and at 2 months, 6 months, 1 year, and 2 years after operation. Results. Follow-up to date is 300 patient-years (average, 0.8 +/- 0.7 years per patient; range, 0.0 to 2.7 years). There were low rates of clinical adverse events. Mean gradient at 6 months was 9.7 +/- 5.3 mm Hg, 7.6 +/- 5.2 mm Hg,6.3 +/- 3.7 mm Hg, 5.8 +/- 3.4 mm Hg, and 4.0 +/- 2.6 mm Hg, respectively, for 19-mm, 21-mm, 23-mm, 25-mm, and 27-mm valves; effective orifice area was 1.6 +/- 0.4 cm(2), 2.0 +/- +/- 0.7 cm(2), 2.2 +/- 0.9 cm(2), 2.5 +/- 0.9 cm(2), and 3.6 +/- 1.3 cm(2), respectively. Indexed effective orifice area was equal to or greater than 1.0 cm(2)/m(2) for all valve sizes. Left ventricular mass index decreased significantly between early postoperative (165.9 +/- 57.1 g/m(2)) and 6-month follow-up (137.9 +/- 41.0 g/m(2); Delta = -28.0 +/- 49.1 g/m(2); p < 0.0001). Conclusions. The St. Jude Medical Regent aortic valve has excellent hemodynamics and early clinical results, with rapid and significant left ventricular mass regression. Long-term clinical assessment is ongoing.