Right-atrial remodeling and residual tricuspid regurgitation after transcatheter edge-to-edge repair

Background Residual tricuspid regurgitation (TR) remains common after transcatheter edge-to-edge repair (TEER) and is consistently associated with worse clinical outcomes. While post-procedural assessment has traditionally focused on right ventricular (RV) systolic function, the relative contribution of right atrial (RA) remodeling to persistent TR remains poorly defined. Objectives To investigate the longitudinal relationship between RA remodeling and residual TR severity after TEER, and to compare its mechanistic and discriminative value with conventional RV systolic indices. Methods We retrospectively studied 131 consecutive patients with severe TR treated by TEER between 2021 and 2025. Comprehensive transthoracic echocardiography was performed at baseline, predischarge, 6-month, and 12-month follow-up. RA remodeling was quantified using the right atrial volume index (RAVI) and right atrial sphericity index (RASI). RV systolic function was assessed using tricuspid annular plane systolic excursion, fractional area change, tissue Doppler–derived systolic velocity, and RV free-wall longitudinal strain. Associations with residual TR severity were explored using Spearman correlation, cumulative ordinal logistic regression, and receiver operating characteristic (ROC) analyses. Results Residual TR severity correlated with RAVI at 6 months (ρ = 0.33, p < 0.001) and with both RAVI (ρ = 0.23, p = 0.030) and RASI (ρ = 0.21, p = 0.047) at 12 months. In multivariable ordinal logistic regression, RAVI emerged as the sole independent determinant of residual TR severity at both timepoints, whereas RV systolic indices were not independently associated. ROC analyses revealed a time-dependent pattern: RASI best discriminated severe residual TR at predischarge, whereas RAVI provided the strongest discrimination at 6 and 12 months (AUC up to 0.76). Conclusions After TEER, right atrial remodeling—particularly persistent volumetric enlargement—dominates the burden of residual TR, while conventional RV systolic measures offer limited explanatory value. These findings reposition the right atrium as a central mechanistic and prognostic target in functional TR management.Central figure