Aortic Valve Replacement with a 19-mm Perimount Magna/Magna Ease Bioprosthesis has Comparable Early and Late Outcomes with Greater Than a 19-mm Prosthesis in Patients with Aortic Stenosis: A Propensity Score-matched Analysis

Objective: In aortic valve replacement (AVR) with a small-sized prosthesis, prosthesis-patient mismatch is of concern. The outcomes after AVR with a 19-mm bioprosthesis have been reported in only a small number of patients. We compared the early and late outcomes after AVR with a 19-mm or with a >19-mm bioprosthesis.

Methods: We retrospectively reviewed 170 patients who underwent AVR with a Perimount Magna/Magna Ease prosthesis (Edwards Lifesciences, Irvine, Calif) for aortic stenosis at our institution from 2008 to 2012. The 19-mm valve was implanted in 109 patients (64%) and the >19-mm valve in 61 patients (36%). Patients with the 19-mm valve had higher proportion of female and less rates of concomitant procedures. The mean follow-up period was 3.6 years. Echocardiography at follow-up was performed in 96 patients (56%). A propensity score analysis matched 1:1 according to AVR with the 19-mm (n = 45) or >19-mm (n = 45) to adjust for baseline variables.

Results: There was no in-hospital death in both the groups. The incidence of stroke (19-mm versus >19-mm: 2.2% versus 0%), IABP/PCPS use (2.2% versus 2.2%), new onset of atrial fibrillation (33.3% versus 40.0%), and prolonged respirator dependence (6.6% versus 4.4%) were similar between the two groups. At follow-up, patients with the 19-mm had significantly higher mean left ventricular aortic pressure gradient and lower effective orifice area index than those with the > 19-mm valve (18.0 ± 6.0mmHg versus 13.6 ± 4.6mmHg, 0.86 ± 0.15cm²/m² versus 1.05 ± 0.27cm²/m², respectively). However, the valve size did not affect reduction in left ventricular mass index at follow-up (19.4 ± 32.0% versus 26.1 ± 16.0%, p = 0.37). The 5-year actuarial survival and freedom from major adverse valve-related event in the 19-mm group were comparable with those in the >19-mm group (92.4% versus 87.9%, p = 0.80, 92.9% versus 85.8%, p = 0.55, respectively). No significant difference was found in the rates of postoperative New York Heart Association class II or higher among the two groups.

Conclusions: Implantation of the 19-mm Magna/Magna Ease prosthesis in aortic position yielded satisfactory clinical and hemodynamic results comparable with the >19-mm prosthesis although mean transvalvular pressure gradient was significantly higher in the 19-mm valve group. The 19-mm valve is a safe and reasonable choice in patients with a small aortic annulus.