Surgery may improve symptoms in these patients, with mitral valve replacement preferred over repair. A subset of pa- tients with severe MR attributable to AF may benefit from mitral valve surgery and concomitant atrial maze procedure (Figure 9). Recommendation-Specific Supportive Text 1. The COAPT trial of transcatheter treatment of secondary MR demonstrated improvement in sur- vival, hospitalization, symptoms, and quality of life in patients with persistent symptoms despite optimization of GDMT who were randomized to TEER, as compared with those randomized to con- tinued GDMT. In contrast, MITRA-FR (Multicentre Randomized Study of Percutaneous Mitral Valve Repair MitraClip Device in Patients With Severe Secondary Mitral Regurgitation) enrolled patients with greater degrees of LV enlargement and less severe MR (mean ERO area 0.31 cm2 ) and reported no benefit of TEER in reducing the composite endpoint of death or hospitalization as compared with medical therapy. In addition, the inclusion criterion in MITRA-FR of an LVESD up to 70 mm represents extreme dilation; in contrast, in the COAPT trial, the mean LVESD was smaller (52 9 mm), and even the LVEDD rarely exceeded 70 mm (mean 62 7 mm). Thus, the enrollment criteria in COAPT trial (LVEF between 20% and 50%, LVESD 70 mm, pulmonary artery systolic pressure 70 mmHg, and persistent symptoms [NYHA class II, III, or IV] while on optimal GDMT) are the current standard selection criteria for TEER for secondary MR. Observational studies have suggested that a greater reduction in MR sever- ity with TEER is associated with greater LV and LA reverse remodeling.1 8,48,49 The exact anatomy and mechanism of MR also needs to be taken into consideration when determining candidacy for transcatheter repair. 2. 