RecruitingDiagnostic testSecondary Mitral Regurgitation Treatment With MitraClip and Assessment by Cardiac Magnetic ResonanceThis is a multi-center, prospective, observational study designed to evaluate the impact of LV myocardial fibrosis extent assessed by CMR on LV reverse remodeling and clinical outcomes post TEER. The target sample will be up to 125 patients enrolled to achieve 100 evaluable at 6 months of follow-up. Enrollment will occur at up to eight centers.