Right atrial reservoir strain predicts tricuspid regurgitation improvement after rhythm control in persistent atrial fibrillation

Background Functional mitral (FMR) and tricuspid regurgitation (FTR) frequently occur in patients with persistent atrial fibrillation (AF) and are largely driven by atrial remodelling resulting in annular dilatation. Rhythm control strategies may promote improvement of valvular regurgitation; however, the role of echocardiographic parameters as predictors of regurgitation improvement remains poorly understood. Purpose To identify echocardiographic predictors of FMR and FTR improvement after restoration of SR in patients with AF. Methods Eighty patients (46% male, mean age 73.7 years [68.0–81.0]) with persistent AF and newly diagnosed at least moderate FMR or FTR undergoing electrical cardioversion or catheter ablation were included. Comprehensive transthoracic echocardiography, including atrial and ventricular strain analysis, was performed at baseline and at 3 months follow-up. Univariable logistic regression analyses were used to identify echocardiographic predictors of FMR and FTR improvement, followed by multivariable models. Results After a mean follow-up of 3.6 ± 9 months, 45 patients (56%) maintained SR. FMR severity significantly improved at follow-up, with the proportion of mild FMR increasing from 24% to 62% (p=0.001). Mild FMR tended to be more frequent in patients in SR compared with those with AF recurrence (69% vs. 25%; p=ns; Figure, A). Similarly to FMR, FTR severity also significantly improved, with mild or no FTR increase from 28% at baseline to 64% at follow-up, while moderate-to-severe FTR decrease from 72% to 36% at follow-up (p=0.002). Patients in SR showed a higher prevalence of mild FTR at follow-up compared with those with recurrent AF (65% vs. 44%, p=ns; Figure, B). In univariable logistic regression analysis, right atrial (RA) reservoir strain was significantly associated with FTR improvement. In multivariable analysis, RA reservoir strain remained an independent predictor of FTR improvement (odds ratio [OR] 1.13, 95% CI 1.01–1.26, p = 0.037; Figure, C). No echocardiographic parameter predicted FMR improvement. Conclusions Rhythm control is associated with significant improvement of functional FMR and FTR, particularly in patients maintaining SR. RA reservoir strain is an echocardiographic parameter predicting FTR improvement in patients with FTR and AF after rhythm control. These findings emphasise the central role of atrial remodelling in FTR and may help refine patient selection for rhythm control strategies.