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

Aims Data are scarce regarding the implications of left atrial (LA) strain (LAS) in patients undergoing transcatheter edge-to-edge repair (TEER) for degenerative mitral regurgitation (MR). We explored pre-, intra-, and post-procedural aspects according to LAS status in this setting. Methods and results A single-centre, retrospective analysis was performed that included 367 individuals (median age 82 years, 62.4% male) referred to isolated, first-time interventions. Stratified by median LAS at baseline (18.5%) and at 1-month post-procedure (29.0%), the cohort was evaluated for all-cause mortality, heart failure (HF) hospitalizations, and significant MR and/or functional incapacitation persistence during the first post-interventional year. Subjects with below-median preprocedural LAS presented more often with acute HF and/or haemodynamic instability, displayed higher interventional risk and atrial fibrillation/flutter prevalence, and had more pronounced chamber dysfunction/dilatation. Procedural features were unaffected by baseline LAS allocation, leading to >97% technical success rate and >80% freedom from above-moderate MR or New York Heart Association Class III–IV in both groups. Worse baseline LAS was associated with higher rates, cumulative incidences, and risks of deaths and/or HF hospitalizations. Per exploratory analysis, the excess composite risk (hazard ratio 2.16, 95% confidence interval 1.16–4.00, P = 0.015) was confined to stable, chronic HF cases with significant LA dilatation. One-month post-procedural LAS directly correlated with its baseline counterpart, and a more impaired value—rather than the change in LAS—conferred heightened deaths/HF readmissions risk. Conclusion Although unrelated to procedural feasibility, safety, or efficacy, worse LAS identifies higher-risk patients prone to experience a less favourable clinical course post-TEER for degenerative MR.