Correlates and prognostic value of left atrial strain in transcatheter edge-to-edge repair for degenerative mitral regurgitation

Background – Data are scarce regarding the implications of left atrial (LA) strain in transcatheter edge-to-edge repair (TEER) patients with degenerative mitral regurgitation (MR). Objective – To explore degenerative MR TEER according to LA strain. Methods – A single-center, retrospective analysis was performed that included 367 individuals (median age 82 years, 62.4% male) undergoing isolated, first-time interventions. Stratified by LA strain at baseline (18.5 (IQR, 16.3-21.8) %) and at 1-month post-procedure (29.0 (IQR, 25.2-33.0) %), eligible cases were evaluated for all-cause mortality, heart failure (HF) hospitalizations, and the persistence of significant MR and/or functional incapacitation along the first postinterventional year. Results – Subjects with below-median preprocedural LA strain presented more commonly with acute HF and/or hemodynamic instability and displayed lower quality of life, higher interventional risk, greater prevalence of atrial fibrillation/flutter, and more pronounced chamber dysfunction and dilatation. Procedural aspects were unaffected by baseline LA strain, leading to >97% technical success rate and >80% freedom from above-moderate MR or NYHA class III-IV in both study groups. Worse LA strain at baseline was associated with higher rates, cumulative incidences, and risks of deaths, HF hospitalizations, and, when accompanied by significant LA dilatation, the composite of the two (HR 2.16, 95% CI 1.16-4.00, p=0.015). One-month postprocedural LA strain directly correlated with its baseline counterpart, and a more impaired value – rather than the change between the two – conferred a heightened risk for the composite of deaths/HF readmissions. Conclusion – Worse LA strain identifies higher-risk patients prone to experience a less favorable course post-TEER for degenerative MR.