Long-term outcome of the mitroflow pericardial bioprosthesis in the elderly after aortic valve replacement

Background and aim of the study: The current trend in Europe and the USA demonstrates an increased number of tissue valves being implanted. However, studies presenting long-term follow up of the Mitroflow pericardial bioprosthesis are relatively scarce. In the present study, the long-term outcome of the Mitroflow in the aortic position was analyzed in a geriatric population using actuarial statistics; risk factors for early and late mortality were also evaluated. Methods: Between 1990 and 1993, 152 elderly (mean age 79.5 ± 3.1 years; range: 75-91 years) patients each received a Mitroflow bioprosthesis implanted in the aortic position. A follow up was conducted in January 2003 and was 100% complete. Concomitant coronary artery bypass grafting was performed in 74 patients (49%). Valve-related outcomes were evaluated using actuarial statistics. Overall survival was compared to that in an age- and gender-matched population. A multivariate analysis of risk factors for mortality was also performed. Results: Actuarial freedom from structural valve deterioration was 99% and 82% at five and 10 years, respectively. Actuarial freedom from stroke, bleeding, prosthetic valve endocarditis and valve explant at 10 years were 80 ± 5%, 94 ± 3%, 93 ± 3% and 89 ± 4%, respectively. Risk factors for mortality during follow up were male gender, small valves (≤21 mm), preoperative NYHA class III /IV, greater age, and long intraoperative perfusion time. Conclusion: The Mitroflow pericardial bioprosthesis demonstrated a good long-term performance after aortic valve replacement, suggesting it to be a feasible option in elderly patients.