Mitral Valve Replacement With a Third-Generation Porcine Valve: An Italian Multicentered Study

Background: Postoperative outcomes of a third-generation porcine bioprosthesis for mitral valve replacement (MVR) have been poorly addressed. The objective of this study was to perform an independent, retrospective, multicenter study on outcomes of patients undergoing MVR with a Mosaic (Medtronic Inc, Minneapolis, MN) porcine bioprosthesis.

Methods: From 1998 to 2011, 805 patients underwent MVR with a Mosaic porcine valve in 11 cardiac centers. There were 465 female patients (58%), and the overall mean age was 73.5 ± 7 years. Associated procedures included coronary artery bypass grafting (201 patients; 24.9%), aortic valve replacement (152 patients; 18.9%), tricuspid annuloplasty (187 patients; 22.3%), and other cardiac procedures (116 patients; 14.4%).

Results: Median follow-up was 44 months (interquartile range, 16 to 63), with a cumulative duration of 2.769 patient-years. Early mortality for isolated elective MVR was 3.8% (12 of 313), and overall early mortality was 7.8% (n = 63). The rate of late mortality was 3.4%/patient-year (95 late deaths). At 10 years, overall survival was 57.4% (95% confidence interval [CI], 48.8% to 67.5%), and cumulative rates of cardiac- and valve-related death were 7.4% (95% CI, 4.8% to 10.1%) and 1.1% (95% CI, 0.2% to 1.9%), respectively. The 10-year cumulative rates of thromboembolic and hemorrhagic events were 6.6% (95% CI, 1.4% to 11.8%) and 3.9% (95% CI, 0.1% to 8%), respectively, and the 10-year cumulative incidence of prosthetic valve endocarditis was 3% (95% CI, 1.2% to 4.9%). Finally, the 10-year cumulative incidences of structural valve degeneration and reoperations were 5.8% (95% CI, 0.2% to 11.5%) and 4.8% (95% CI, 0.7% to 10.3%), respectively.

Conclusions: This independent, multicenter, retrospective study indicated that the Mosaic porcine bioprosthesis for MVR provides satisfactory results in terms of both early and long-term outcomes up to 14 years from its implantation.