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

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.

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.

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 (< or = 21 mm), preoperative NYHA class III/IV, greater age, and long intraoperative perfusion time.

The Mitroflow pericardial bioprosthesis demonstrated a good long-term performance after aortic valve replacement, suggesting it to be a feasible option in elderly patients.