Hemodynamic performance and incidence of patient-prosthesis mismatch of the complete supraannular Perimount Magna bioprosthesis in the aortic position

Background: Complete supraannular placement and smaller stent design allow the implantation of a Perimount Magna bioprosthesis with a larger inner diameter than that of a standard Perimount. This study compares the hemodynamic performance and the incidence of patient-prosthesis mismatch (PPM) of both prostheses. Methods: 128 patients underwent aortic valve replacement, receiving either a Magna (n = 57) or a standard (n = 71) prosthesis. Inner aortic annulus diameter was measured intraoperatively by a hegar dilator to match echocardiographically obtained results to the annulus diameter instead of matching them to labelled valve size. Results: The Magna was significantly superior with respect to mean pressure gradient and effective orifice area in patients with an annulus diameter of 22 - 23 mm. In patients with an annulus diameter < 22 mm or > 23 mm, there was a non-significant trend towards superior hemodynamics in the Magna group. Severe PPM (effective orifice area index <= 0.65 cm(2)/m(2)) Was present in 11.1% (Magna) vs. 42.1% (Standard) of patients with an annulus diameter < 22 mm; in 0% (Magna) vs. 13.8% (Standard) with an annulus diameter of 22-23 mm; no PPM was seen in patients with annulus diameter > 23 mm in both groups. Conclusions: The Perimount Magna had a significantly reduced incidence of patient-prosthesis mismatch and superior hemodynamics compared to the standard Perimount.