Porcine versus bovine bioprosthetic valves in mitral position: does choice really matter?

Abstract

Bioprosthetic valves are increasingly used for surgical mitral valve replacement (MVR). The long-term outcomes of bovine (BoMVR) vs porcine (PoMVR) remain an enigma regarding the durability. This study aims to examine the outcomes of BoMVR vs PoMVR. A retrospective analysis of all bioprosthetic MVRs, with concomitant procedures, at a single tertiary referral institution from January 2005 to December 2008 was conducted. Procedures were classified as BoMVR or PoMVR. The age group was from 40 to 70years. We identified 154 BoMVR patients and 120 PoMVR patients after matching the two groups with respect to age, sex, valve size and concomitant procedures. Kaplan-Meier survival analysis model was used for corresponding statistical analysis. Freedom from reoperation (all cause), freedom from non-structural valve deterioration, freedom from structural valve deterioration, freedom from heart failure and freedom from infective endocarditis were 96.4 ± 0.08, 97.1 ± 0.07, 96.4 ± 0.08%, 98.2 ± 0.07, and 98.6 ± 0.06% in PoMVR, respectively, and 92.6 ± 0.09, 91.6 ± 0.08, 90.6 ± 0.09, 94 ± 0.08, and 92.8 ± 0.08% in BoMVR groups, respectively, at the end of 10-year follow-up (mean follow up of 6.2 ± 2.3years). Overall, 20 (12.9%) patients were lost to follow-up in the BoMVR and 15(12.5%) patients in the PoMVR groups for a global follow-up of 87.1%. For patients undergoing MVR with a bioprosthetic valve, the choice of PoMVR vs BoMVR favours more in favour of PoMVR as evidenced by the outcome results. Probably long-term follow-up with more patients might throw further light on the debatable topic.