Hemodynamic performance of the new St. Jude Medical Epic Supra porcine bioprosthesis in comparison to the Medtronic Mosaic on the basis of patient annulus diameter.

BACKGROUND AND AIM OF THE STUDY

The St. Jude Medical Epic Supra (ES) valve is a new porcine bioprosthesis designed for complete supra-annular implantation. To date, no in-vivo data regarding the hemodynamic and clinical performance of this valve are available. The study aim was to compare the hemodynamic performance of the ES valve with the completely supra-annular Medtronic Mosaic (MM) porcine valve.

METHODS

Between July 2000 and April 2006, 83 patients (39 males, 44 females) underwent aortic valve replacement with either the ES (n = 44) or MM (n = 39) bioprosthesis. Hemodynamic performance was evaluated echocardiographically at six months postoperatively. Comparison between the valves was performed by dividing the patient groups according to their intraoperatively measured tissue annulus diameter rather than the labeled valve size.

RESULTS

The internal diameter and sewing ring diameter differed in ES and MM valves with the same labeled size. For example, in valves labeled '23' the internal diameter/sewing ring diameters were 21.5 and 29.3 mm in the ES valve versus 20.5 and 30 mm in the MM. The mean pressure gradients (MPG) for patients with ES or MM valves were 15.5 +/- 4.5 or 14.8 +/- 5.1 mmHg for annulus diameter < or =22 mm, 14.6 +/- 6.4 or 13.9 +/- 3.6 for annulus diameter 23-24 mm, and 15.3 +/- 3.8 or 13.4 +/- 4.2 mmHg for annulus diameter > or =25 mm. No significant differences were identified in the hemodynamic data, including MPG, effective orifice area (EOA) and effective orifice area index (EOAI). The incidence of moderate or severe patient-prosthesis mismatch (PPM) was 40% (n = 18) and 5% (n = 1) in patients with ES valves, and 26% (n = 10) or 23% (n = 9) in patients with MM valves (p = 0.01). In patients with an annulus size < or =22 mm, severe PPM occurred in 29% (n =5) of patients with MM valves but in none of those with ES valves.

CONCLUSION

The hemodynamic performance of the ES valve was comparable to that of the well-established MM valve. The incidence of severe PPM was lower in patients with ES valves than MM valves, presumably due to the somewhat larger EOA values in patients with a small aortic annulus (<25 mm).