Long-Term Outcomes and Durability of the Mitroflow Aortic Bioprosthesis.

BACKGROUND: This study aims to determine the incidence and causes of structural valve deterioration (SVD) among all models of Mitroflow bioprostheses (A12/LX/DL), as well as to define their long-term clinical and hemodynamic performance.

METHODS AND RESULTS: We retrospectively reviewed a series of 1023 patients who underwent aortic valve replacement with Mitroflow bioprostheses between 2001 and 2014. A small aortic root was found in 22.4% of patients. There were two cases of severe patient-prosthesis mismatch. Only 31 patients developed SVD. The rate of incidence was 8.1 cases per 1000 patient-years. Cumulative incidence of SVD was 1.4% and 3% at five and 10 years, respectively. Freedom from SVD was 97.4% and 88.2% at five and 10 years, respectively. Anticalcification phospholipid reduction treatment (PRT) for model DL was a protective factor for SVD. Multivariable analysis confirmed age <70 years and use of 19 mm valve as independent predictors of SVD. Cumulative survival was 76.6% at five years and 42.3% at 10 years (mean follow-up 3.8 ± 3.1 years). In multivariable analysis, neither the use of small aortic prosthesis (p = 0.18) nor the occurrence of SVD (p = 0.85) was found to be independent predictors of long-term survival.

CONCLUSIONS: Mitroflow valves demonstrate an acceptable rate of SVD and satisfactory long-term hemodynamic performance, particularly in patients with small aortic roots, age >70 years, and cases with severe left ventricular hypertrophy. PRT might contribute to improved long-term durability. doi: 10.1111/jocs.12726 (J Card Surg 2016;31:264-273).