The importance of preservation of the subvalvular apparatus (PSVA) during mitral valve replacement (MVR) in non-rheumatic mitral valves is well recognized. Our aim was to analyse the impact of PSVA in MVR for rheumatic valves on long-term survival.METHODS
From January 1992 to December 2012, 605 consecutive patients with rheumatic mitral valve disease were submitted to MVR. PSVA (limited to the posterior leaflet) was achieved in 224 (37.7%) patients. Follow-up was 4259 patient-years, and complete for 97% of the patients. Propensity score analysis was introduced to reduce selection bias.RESULTS
Patients with PSVA were slightly older (61.9 vs 59.8 years, P = 0.014), with lower incidence of calcification (54.9 vs 63.0%, P = 0.05), pure mitral stenosis (29.9 vs 38.9%, P = 0.014) and history of rheumatic fever (44.6 vs 53.9%, P = 0.028). Mechanical prostheses were more frequently implanted in the Non-PSVA group (75.1 vs 65.6%, P = 0.013). Thirty-day mortality was 1.1%. Late survival rates at 5, 10 and 18 years were 86.6 ± 2.0, 70.8 ± 3.2 and 48.0 ± 5.1%, respectively, with no difference between groups. Both groups had compromised late survival when compared with the general population (age and gender matched, P < 0.001). Only age, large left atrium, pulmonary hypertension and ‘pure’ MR appeared as independent predictors for late mortality. There was no difference regarding adverse valve-related events between groups.CONCLUSIONS
Patients submitted to MVR for rheumatic mitral valve disease have a poor prognosis, independently of having the subvalvular apparatus preserved. PSVA did not improve late survival in this setting.