Do differences in early hemodynamic performance of current generation biologic aortic valves predict outcomes 1 year following surgery?

Abstract

Objective: Small early postoperative hemodynamic differences were noted in a randomized comparison of 3 current-generation bioprosthetic aortic valves. Whether these differences persist and influence clinical outcomes 1 year following implantation is unknown.

Methods: Three hundred adults with severe aortic stenosis undergoing valve replacement were randomized to receive the Epic (St Jude, St Paul, Minn) (n = 99), Magna (Edwards LifeSciences Inc, Irvine, Calif) (n = 100), or Mitroflow (Sorin Biomedica Spa, Saluggio, Italy) (n = 101) bioprostheses. Hemodynamic valve performance was examined by echocardiography at 1 year, and clinical outcomes were assessed in 241 patients (79 Epic, 77 Magna, and 85 Mitroflow; P = .437).

Results: Mean age was 75 ± 8 years and 164 were men (68%). Between dismissal and 1 year there were 9 deaths (3.7%) (Epic: 3.7%, Magna: 5.0%, and Mitroflow: 2.3%; P = .654), 6 episodes of heart failure (2.5%) (Epic: 1.3%, Magna: 1.3%, and Mitroflow: 5.8%; P = .265), 27 instances of atrial fibrillation/flutter (11.2%) (Epic: 8.1%, Magna: 11.0%, and Mitroflow: 7.9%; P = .577) and no strokes/transient ischemic attacks. One-year echocardiography demonstrated small hemodynamic differences between Epic, Magna, and Mitroflow bioprostheses in mean gradient (15.2 ± 5.5, 12.3 ± 4.3, and 16.2 ± 5.7 mm Hg, respectively; P < .001) and indexed aortic valve area (0.93 ± 0.28, 1.04 ± 0.28, and 0.96 ± -0.26 cm(2)/m(2), respectively; P = .015). Several early trends persisted when stratifying data by echocardiographic annulus diameter, universal annulus size, and implant size, particularly with annular size ≥23 mm. Overall left ventricular mass index regression between dismissal and 1 year was -16.5 ± 28.1 g/m(2), and was similar among groups (P = .262). There were no aortic valve reoperations.

Conclusions: Despite midterm persistence of small hemodynamic differences amongst current-generation porcine and pericardial aortic valves, our prospective randomized comparison reveals that clinical outcomes and mass regression are equivalent between devices at 1 year. These encouraging trends must continue to be assessed during longitudinal follow-up.