Late Outcomes of Porcine and Pericardial Bioprostheses after Mitral Valve Replacement in 1162 Patients

BACKGROUND Debate continues regarding the superiority of porcine versus pericardial bioprostheses, and data relevant to this comparison are scant. We therefore compare late survival and structural valve deterioration of porcine and pericardial mitral valve prostheses. METHODS Adults undergoing mitral valve replacement with one first-generation porcine valve model and one pericardial valve line were reviewed from our prospectively-maintained institutional database between 1976 and 2020. Multivariable regression and Cox proportional hazards analysis were used to compare late outcomes. RESULTS Of 1162 consecutive patients, 612 (53%) received porcine valves and 550 (47%) received pericardial valves. At 10 years, patient survival (porcine 36±2%, pericardial 38±3%, P=0.5) and cumulative incidence (CI) of mitral valve structural deterioration (porcine 18±2%, pericardial 19±3%, P=0.3) were similar. The structural failure mode was more likely severe mitral stenosis in pericardial valves (35/50(70%) versus 38/106(36%), P<0.001), and more likely severe mitral regurgitation in porcine valves (80/106(75%) versus 19/50(38%), P<0.0001). After adjustment, structural deterioration was associated with younger patient age (P<0.001), but not valve type. At 10 years, porcine valves demonstrated a higher CI of mitral reoperation (19±2% vs 9±2%, P<0.001) and reoperation for structural deterioration (15±1% vs 6±2%, P=0.007). CONCLUSIONS We demonstrate similar rates of 10-year survival and structural deterioration with porcine and pericardial bioprosthetics in mitral valve replacement. This study suggests a lack of major improvement in durability of mitral bioprosthetic valves over time. Failure mode may have greater influence on surgeon decision-making of valve choice.