Objective: Restrictive mitral annuloplasty (RMA) can often improve heart failure symptoms and induce left ventricular (LV) reverse remodelling in patients with non-ischaemic dilated cardiomyopathy (DCM) and functional mitral regurgitation. However, it is unknown whether the observed LV reverse remodelling translates into better outcomes or not.
Method: Fifty patients with advanced non-ischaemic DCM (age, 64 ± 10 years, 74% men) underwent RMA and were followed up with a mean of 2 years. Preoperatively, all had 3 to 4+ functional mitral regurgitation (MR), an ejection fraction (EF) of 26 ± 8.6 %, an indexed LV end-systolic volume (LVESVI) of 112 ± 47 ml/m(2). All patients received complete semi-rigid undersized ring annuloplasty. Correlations between early reduction in LVESVI at 1 month after the operation and mid-term clinical outcomes were analysed.
Result: There was no 30-day mortality. LVESVI significantly decreased to 96 ± 53 ml/m(2) and LVEF improved to 31 ± 15%. During follow-up, 16 (32%) recurred heart failure, of whom 7 (14%) died. The receiver operating characteristic (ROC) curve found that a reduction in LVESVI >8.3% had a sensitivity of 80% and a specificity of 78% in predicting all adverse events. With this cut-off value, there were 30 (60%) responders to reverse remodelling. Responders had significantly better survival (96.4 versus 68.7%, P = 0.007) and freedom from heart failure rate (85.4 versus 31.8%, P = 0.0003) than non-responders at 3 years. In a 1-year follow-up echocardiographic study, non-responders had shown no significant LV reverse remodelling with greater degree of residual MR than responders.
Conclusion: The extent of early LV reverse remodelling is related to mid-term mortality, heart failure events and late reverse remodelling and repair durability after RMA for non-ischaemic DCM.