Secondary mitral regurgitation: percutaneous edge-to-edge repair on the cutting edge?

Abstract

Secondary mitral regurgitation commonly complicates heart failure. Although the evidence for its management is most robust for treating the underlying cardiomyopathy, treatment aimed at additionally reducing the severity of mitral regurgitation with a percutaneous edge-to-edge device, MitraClip, has recently emerged. Despite the use of contemporary evidence-based heart failure therapies, patients with secondary mitral regurgitation and heart failure continue to remain at high risk for adverse clinical events; in both the MITRA-FR and COAPT trials, an extremely high event rate was evident in the medically managed arms over the respective 12-24-month follow-up. Data supporting the use of MitraClip to mitigate adverse outcomes in secondary mitral regurgitation is, however, conflicting. In MITRA-FR no difference was noted between MitraClip compared with the medically managed arm for the composite of all-cause death or heart failure hospitalization at 12 months. However, in COAPT, a significant reduction in the rate of heart failure re-hospitalization over 2 years was evident with MitraClip compared with medical therapy alone. Recommendations exist for the use of MitraClip in patients with primary mitral regurgitation and prohibitive surgical risk. However, with the divergent results of two recent high-quality randomized trials, its role in patients with secondary mitral regurgitation remains controversial.