Influence of Mitroflow bioprosthesis structural valve deterioration on cardiac morbidity

Background: This study investigated the extent and nature of cardiac morbidity and cause of mortality in patients with Mitroflow structural valve deterioration (SVD). Methods: A retrospective study was performed examining the medical records of patients who had received Mitroflow bioprosthesis between February 2001 and April 2014 and died during this period. A total of 211 patients were identified and included in the analyses. To determine the cause of mortality, cases were divided into three predefined groups: cardiovascular death due to SVD (group 1), cardiovascular death with no SVD (group 2) and non-cardiovascular death without SVD (group 3). Results: Overall mortality in this study was 7.6% at 1 year, 46.4% at 5 years and 97.2% at 10 years. In group 1, 53 patients (25%) died; in group 2, 59 patients (28%) died; and in group 3, 99 patients (47%) died. Hospitalisation for congestive heart failure was observed in 49.1% in the SVD group vs. 10.2 and 13.1% in the two other groups, p<0.001. Hospitalisation for endocarditis was also significantly higher in the SVD group (11.3%) than in the two other groups (6.8 and 0%), p<0.05. Hospitalisation due to myocardial infarction, cerebral stroke, arrhythmia or other cardiac-related diseases was not significantly different between groups. Conclusion: Structural valve deterioration in Mitroflow bioprosthesis was associated with a high prevalence of hospital admissions due to congestive heart failure and endocarditis. Patients with Mitroflow bioprosthesis should be systematically and routinely followed with echocardiography, and reoperation should be considered if SVD has developed.