Interventions for Secondary Mitral Regurgitation in Patients With Heart Failure: A Network Meta-Analysis of Randomized Controlled Comparisons of Surgery, Medical Therapy and Transcatheter Intervention

Abstract

Mitral regurgitation (MR) in heart failure (HF) notoriously carries a poor prognosis. While there are multiple interventional options for treatment, the optimal intervention remains controversial. Therefore, we aimed to evaluate the efficacy and safety of surgery, medical therapy, and transcatheter intervention in secondary MR. A systematic database search was performed to identify all randomized controlled trials (RCTs) that evaluate various interventions for secondary MR. We performed a Bayesian network meta-analysis to calculate odd ratios (ORs) and 95% credible intervals (CIs). The primary endpoint was all-cause mortality. Secondary endpoints were moderate-severe MR, HF-hospitalizations, and freedom from severe HF symptoms. We identified 12 RCTs (2316 total patients; age 67.6 ± 11; 63% males, and 74% with ischemic cardiomyopathy). There was a significant reduction of mortality at 24-months with transcatheter leaflet repair compared with medical therapy (OR = 0.57; 95% CI = 0.34-0.96). However, there were no significant differences among the competing treatments in all-cause mortality at the earlier time points of 30-days or 12-months (P > 0.05). Recurrent moderate-severe MR was significantly less with valvular interventions compared with medical therapy (P < 0.05), but there were no differences in the rates of HF-hospitalizations or persistent severe HF symptoms between the competing interventions (P > 0.05). Among patients with HF and secondary MR, transcatheter leaflet repair was associated with significantly reduced 24-month mortality compared with medical therapy. Valvular interventions were associated with lower rates of recurrent moderate-severe MR, but non-significant improvements in clinical outcomes. Further long-term studies are needed to identify the best route of intervention for secondary MR.