Expanding the Spectrum of TEER Suitability: Evidence From the EXPAND G4 Post Approval Study

Background: Anatomical and clinical criteria to define mitral transcatheter edge-to-edge repair (TEER) “unsuitability” have been proposed on the basis of a Heart Valve Collaboratory consensus opinion from physician experience with early-generation TEER devices but lacked an evidence-based approach. Objectives: The aim of this study was to explore the spectrum of TEER suitability using echocardiographic and clinical outcomes from the EXPAND G4 real-world postapproval study. Methods: EXPAND G4 is a global, prospective, multicenter, single-arm study that enrolled 1,164 subjects with mitral regurgitation (MR) treated with the MitraClip G4 System. Three groups were defined using the Heart Valve Collaboratory TEER unsuitability criteria: 1) risk of stenosis (RoS); 2) risk of inadequate MR reduction (RoIR); and 3) subjects with baseline moderate or less MR (MMR). A TEER-suitable (TS) group was defined by the absence of these characteristics. Endpoints included independent core laboratory–assessed echocardiographic characteristics, procedural outcomes, MR reduction, NYHA functional class, Kansas City Cardiomyopathy Questionnaire score, and major adverse events through 30 days. Results: Subjects in the RoS (n = 56), RoIR (n = 54), MMR (n = 326), and TS (n = 303) groups had high 30-day MR reduction rates (≤1+: RoS 97%, MMR 93%, and TS 91%; ≤2+: RoIR 94%). Thirty-day improvements in functional capacity (NYHA functional class I or II at 30 days vs baseline: RoS 94% vs 29%, RoIR 88% vs 30%, MMR 79% vs 26%, and TS 83% vs 33%) and quality of life (change in Kansas City Cardiomyopathy Questionnaire score: RoS +27 ± 26, RoIR +16 ± 26, MMR +19 ± 26, and TS +19 ± 24) were safely achieved in all groups, with low major adverse events (<3%) and all-cause mortality (RoS 1.8%, RoIR 0%, MMR 1.5%, and TS 1.3%). Conclusions: Patients previously deemed TEER unsuitable can be safely and effectively treated with the mitral TEER fourth-generation device.