Impact of valve type on outcomes after redo mitral valve replacement in patients aged 50 to 69 years

Abstract

Little data are available with regard to valve selections in redo valvular surgery. We investigated the impact of valve types on late outcomes after redo mitral valve replacement (MVR). We retrospectively reviewed 66 patients aged 50-69 (mean age 62.2 ± 5.1) years who underwent redo MVR over the past 25 years. In redo MVR, 46 (69.7%) redo procedures were the 1st redo valvular surgeries, 16 (24.2%) were 2nd redos, 3 (4.5%) were 3rd redos and 1 was a 4th (1.5%) redo. We classified 66 patients into 2 groups: mechanical MVR group (M-MVR, n = 44) and biological MVR group (B-MVR, n = 22). The mean follow-up period was 8.2 ± 6.3 years. Hospital mortality rates were 3.3% in M-MVR and 9.7% in B-MVR (P = 0.3328). Survival rates in M-MVR and B-MVR at 5 and 10 years were 93.0 ± 4.8% vs 76.0 ± 10.5% and 77.6 ± 9.1% vs 51.3 ± 13.7%, respectively (log-rank test, P = 0.0072). Late death occurred in 7 patients in M-MVR and 9 in B-MVR. Freedom rates from valve-related events in M-MVR and B-MVR at 5 and 10 years were 100.0 ± 0.0% vs 76.5 ± 10.3% and 93.3 ± 6.4% vs 52.4 ± 13.6%, respectively (log-rank test, P < 0.0001). No bleeding and thromboembolic events were observed in M-MVR, whereas gastrointestinal bleeding (n = 1), subarachnoid haemorrhage (n = 1) and cerebral infarction (n = 2) were observed in B-MVR. A predictor of late death was a biological valve in redo MVR (P = 0.0206, hazard ratio = 3.402, 95% confidence interval 1.207-9.591). It would seem that redo MVR using a mechanical valve was associated with better early and late outcomes in this age group.