Implantation of one, two or multiple MitraClip™ for transcatheter mitral valve repair: insights from a 1824-patient multicenter study

BACKGROUND: Transcatheter mitral valve repair (TMVR) with MitraClipTM (Abbott Laboratories; Abbott Park, IL, USA) is an established treatment for mitral regurgitation (MR). More than one MitraClipTM may be implanted if a single one does not reduce MR adequately. We aimed to appraise the outlook of patients undergoing implantation of one, two or multiple MitraClipTM for TMVR. METHODS: Exploiting the ongoing prospective GISE Registry of Transcatheter Treatment of Mitral Valve Regurgitation (GIOTTO) Study dataset, we compared patients, procedural details and outcomes distinguishing those receiving one, two or multiple MitraClipTM. The primary endpoint was the composite of 1-year cardiac death or rehospitalization for heart failure. Additional endpoints included all cause death, surgical mitral repair, and functional class. Multivariable adjusted Cox proportional hazard analysis was used for confirmatory purposes. RESULTS: As many as 1824 patients were included: 718 (39.4%) treated with a single MitraClipTM, and 940 (51.5%) receiving two MitraClipTM, and 166 (9.1%) receiving three or more. Significant differences were found for baseline features, including age, female gender, diabetes mellitus, hypertension, chronic obstructive pulmonary disease, prior myocardial infarction, atrial fibrillation, permanent pacemaker, cardiac resynchronization therapy, implantable cardioverter defibrillator, and prior mitral valve repair (all P<0.05). Several imaging features were also different, including left ventricular dimensions, MR severity and proportionality, mitral valve area, flail leaflet, and pulmonary vein flow (all P<0.05). Among procedural features, significant differences were found for anesthesia type, MitraClipTM type, fluoroscopy, device, and operat ing room times, postprocedural mitral gradient, residual MR, smoke-like effect, device success partial detachment and surgical conversion (all P<0.05). In-hospital death occurred more frequently in patients receiving multiple MitraClipTM, and the same applied severe residual MR (all P<0.05). Mid-term follow-up (15±13 months) showed significant differences in the risk of death, cardiac death, rehospitalization for heart failure, and their composites, mainly, but not solely, associated with multiple MitraClipTM (all P<0.05). Adjusted analysis confirmed the significantly increased risk of composite adverse events when comparing the multiple vs. single MitraClipTM groups (P=0.014 for death and rehospitalization, P=0.013 for cardiac death or rehospitalization). CONCLUSIONS: Implantation of one or two MitraClipTM is associated with favorable clinical outcomes. Conversely, bail-out implantation of three or more MitraClipTM may portend a worse long-term prognosis.