HEMODYNAMICS AND LEFT-VENTRICULAR MASS REGRESSION FOLLOWING IMPLANTATION OF THE TORONTO SPV STENTLESS PORCINE VALVE

Stentless tissue valves may provide more favorable hemodynamics than c onventional stented valves. Hemodynamic findings from a large multicen ter trial have not been previously reported. The present report descri bes the hemodynamic findings from a multinational, multicenter study a fter implantation of the Toronto SPV valve. A total of 577 patients un derwent aortic valve replacement with the Toronto SPV valve at 12 site s in 3 countries. Echocardiograms were recorded in the early post-oper ative period, 3 to 6 months after surgery, 1 year after surgery, and y early thereafter, with follow-up to 3 years. Gradients decreased and e ffective orifice area increased in the months after surgery. One year after surgery, mean gradient for valve sizes 20 to 22, 23, 25, 27, and 29 mm was 7.3 +/- 4.4, 7.4 +/- 4.5, 6.1 +/- 3,3, 4.9 +/- 2.4, and 4.0 +/- 2.1 mm Hg, respectively; effective orifice area was 1.3 +/- 0.7, 1.5 +/- 0.5, 1.7 +/-: 0.4, 2.0 +/- 0.4, and 2.4 +/- 0.6 cm(2), respect ively. There was a very low prevalence of significant aortic regurgita tion at all time periods. There was significant left ventricular (LV) mass regression between the early and 3- to 6-month periods and betwee n the 3- to 6-month and 1-year postoperative periods. The Toronto SPV valve has an excellent hemodynamic profile supported by significant re gression of LV hypertrophy in the year after implantation. Data throug h 3 years demonstrates maintenance of Pow gradients and freedom from s ignificant aortic regurgitation. (C) 1998 by Excerpta Medica, Inc.