Mitroflow pericardial valve prosthesis in the aortic position: An analysisof long-term outcome and prognostic factors

Background and aim of the study: Pericardial valves combine optimal hemodyn amic properties with limited durability. To describe the long-term performa nce of Mitroflow pericardial valves in the aortic position, outcome and ris k factors up to 12 years after implantation were analyzed. Methods: A retrospective study, based on follow up of 1,029 patients who re ceived 1,044 Mitroflow pericardial valves in the aortic position between Fe bruary 1985 and December 1996, was performed. Follow up was 98.2% complete. Average follow up was 3.79 years. Mean patient age was 75.2 +/- 6.5 years (range: 27.9-90.9 years). At surgery, 86.3% of patients were aged over 70 y ears. Among patients, 482 (46.8%) had concomitant operations. Results: Results (+/- SE) are given for evident and possible tin parenthese s) valve-related events; the latter included all reported postoperative str okes and sudden deaths. Actuarial event-free rates after 5 and 10 years res pectively were: structural valve deterioration: 99.2 +/- 0.5% and 77.6 +/- 4.4%; non-structural valve deterioration: 99.7 +/- 0.2% and 99.7 +/- 1.2%; valve-related complications: 95.7 +/- 0.9% and 73.5 +/- 4.0% (5 years 90.1 +/- 1.2%, 10 years 57.0 +/- 4.3%); endocarditis: 96.6 +/- 0.8% and 92.6 +/- 1.6%; explantation: 98.6 +/- 0.5% and 80.1 +/- 3.9%; cerebrovascular accid ent 95.2 +/- 0.9% and 82.5 +/- 3.5%; embolism 99.9 +/- 0.1% and 99.9 +/- 0. 5%; bleeding 99.8 +/- 0.2% and 99.8 +/- 1.3%; overall mortality 69.9 +/- 1. 8% and 35.3 +/- 3.0%; valve-related death 97.5 +/- 1.1% and 95.1 +/- 4.2% ( 5 years 91.9 +/- 1.4%, 10 years 76.1 +/- 3.2%). The 30-day mortality rate w as 4.1%. Patients aged 70 years or more with valve diameters of less than o r equal to 23 mm showed 10-year freedom rates of 85.8 +/- 4.6% for structur al valve degeneration and 95.1+/-1.2% for evident valve-related death. The detailed risk factor analysis showed results that were in accordance with c linical experience. Conclusion: Long-term results with Mitroflow pericardial valves in the aort ic position compare well with those for other widely used bioprostheses, es pecially in patients aged greater than or equal to 70 years and with small aortic root diameters (less than or equal to 23 mm).