A meta-analysis of MitraClip combined with medical therapy versus medical therapy alone for treatment of mitral regurgitation in heart failure patients

AimsSurvival benefit of percutaneous mitral valve repair with the MitraClip over conservative treatment of functional mitralregurgitation (MR) remains unclear. The purpose of this meta-analysis is to compare survival outcomes of MitraClip with thoseof medical therapy in patients with functional MR.Methods and resultsA comprehensive literature search of PubMed, MEDLINE, and Google Scholar was conducted includingstudies evaluating MitraClip vs. medical therapy with multivariate adjustment and with>80% of patients with functional MR.Death from any cause was the primary endpoint, while freedom from readmission was the secondary one, evaluated with ran-dom effects. These analyses were performed at study level and at patient level including only functional MR when available,evaluating the effect of MitraClip in different subgroups according to age, ischaemic aetiology, presence of implantablecardioverter defibrillator/cardiac resynchronization therapy, and left ventricular ejection fraction and volumes. We identifiedsix eligible observational studies including 2121 participants who were treated with MitraClip (n= 833) or conservative ther-apy (n= 1288). Clinical follow-up was documented at a median of 400 days. At study-level analysis, MitraClip, when comparedwith medical therapy (P= 0.005), was associated with significant reduction of death (P= 0.002) and of readmission due tocardiac disease. At patient-level analysis, including 344 patients, MitraClip confirmed robust survival benefit over medical ther-apy for all patients with functional MR and among the most important subgroups.ConclusionsCompared with conservative treatment, MitraClip is associated with a significant survival benefit. Importantly,this superiority is particularly pronounced among patients with functional MR and across all the main subgroups.