Background and aim of the study: Stentless porcine valves are considered to have a superior hemodynamic performance when compared with stented bioprostheses. In the present study we report our initial experience with the Edwards Prima stentless valve (EPSV), focusing on the hemodynamic performance of this device evaluated by means of transthoracic two-dimensional (2D) Doppler echocardiography.
Methods: Between December 1994 and August 1995, 23 patients underwent aortic valve replacement with the EPSV implanted in the subcoronary position. Evaluation of hemodynamic performance of the EPSV was assessed before discharge (one week) and at six months follow up by means of transthoracic 2D echocardiography.
Results: There were no operative deaths and no major postoperative complications. Hemodynamic data were available for comparison at one week and six months in 18 patients (23 mm, n = 8; 25 mm, n = 10). For 23 mm EPSV, peak gradient varied from 42.7 +/- 10.2 mmHg at one week to 29.7 +/- 9.8 mmHg at six months (p = 0.01); for 25 mm EPSV, peak gradient varied from 33.6 +/- 10.6 mmHg at one week to 29.5 +/- 6.5 mmHg at six months (p = N.S.).
Conclusions: The EPSV, when used in the subcoronary position, has been associated with high early transprosthetic gradients which only partly regress at six months. Gradients are probably caused by the inward folding of the Dacron cloth beneath the right coronary ostium and were recorded especially in patients with aortic stenosis in whom the right coronary ostium was close to the aortic annulus. In such patients alternative implantation techniques should be considered.