Is catheter ablation in atrial fibrillation patients with functional tricuspid regurgitation as effective as in patients with functional mitral regurgitation?

Abstract Background Patients with isolated functional tricuspid regurgitation (FTR) frequently have atrial fibrillation (AF). The prognosis is poor, with some requiring transcatheter or surgical tricuspid valve replacement. Catheter ablation (CA) is known to be effective for AF with functional mitral regurgitation (FMR), however, the effectiveness for AF with FTR remains unclear. Purpose To investigate the efficacy of CA in patients with FTR compared with patients with FMR. Methods We retrospectively studied 117 patients (57 females, 72±9 years) with moderate (1. 5~2) to severe (2. 5~3) FTR and FMR among 1386 patients who underwent first CA for AF between 2014 and 2023. Transthoracic echocardiography was performed before and one year after CA to quantitatively assess conventional echocardiographic parameters and the severity of TR and MR. Results Twenty-eight patients with FTR are older (75±6 vs. 71±9 yrs, p=0. 0182) and more likely to be female 19 (68%) vs. 38 (43%) yrs, p=0. 0192 than 89 patients with FMR. There were no differences in ablation procedures between patients with FTR and FMR. During the one-year follow-up period after CA, one patient received Mitra-Clip implantation six months later, and the AF-free survival rate after CA in FTR patients was not different from that in FMR patients (72% vs. 82%) (Figure 1). One year later, the degree of FTR (1. 79±0. 32 to 1. 34±0. 57, p. 0001) had improved to the same level as FMR (1. 74±0. 35 to 1. 26±0. 63, p=0. 0014) (Figure 2). The degree of improvement in TR in FTR patients was higher in the non-recurrent AF group (1. 86±0. 30 to 1. 22±0. 49 vs. 1. 71±0. 39 to 1. 64±0. 69, p=0. 0321). However, in the FMR patient group, there was no difference in the degree of improvement in MR between the recurrent AF and non-recurrent AF groups (1. 80±0. 37 to 1. 31±0. 64 vs. 1. 61±0. 21 to 0. 95±0. 47, p=0. 2342). Conclusion CA is as effective in improving TR severity in AF patients with FTR as it is in improving MR severity in AF patients with FMR. The improvement in FTR severity after CA might be more associated with sinus rhythm maintenance than the improvement in FMR severity.