Background: Tricuspid regurgitation (TR) is a risk factor for atrial fibrillation (AF) by causing volume overload of the right atrium (RA), RA remodeling, and promotion of an AF substrate. On the other hand, AF may lead to tricuspid leaflet malcoaptation by tricuspid annulus dilatation, which could be possibly reverted after achieving rhythm control by means of pulmonary vein isolation (PVI). We investigated whether the presence of TR affects the outcome of PVI for AF. 

Methods: We enrolled patients with symptomatic AF undergoing PVI between 2018 and 2022 with echocardiographic data at baseline and 6-month follow-up. Patients were categorized according to severity of TR at baseline. The primary endpoint was defined as the recurrence of atrial arrhythmias after PVI after a 3-month blanking period. Key secondary endpoint was the change of TR severity following PVI. 

Results: A total of 247 patients (mean age 67.3±9.5 years, 61% male, 57% paroxysmal AF) were included. At baseline, most patients had a preserved left-ventricular ejection fraction (mean left-ventricular ejection fraction 55±8.4%), a dilated right (RA area 20.3±5.7 cm²) and left atrium (mean LASV-index 44.2±12.5 mL/m²). Moderate mitral regurgitation (MR) was found in 40 patients (16.1%). Moderate to severe TR (II-IV°) was documented in 13.7% of the patients at baseline, which was associated with older age (72.1 vs. 66.5 years, p=0.002), female sex (62% vs. 35%, p=0.002), and higher rates of persistent AF (59% vs. 41%, p=0.031), as well as concomitant moderate MR (50% vs. 11%, p<0.001) compared to patients with TR 0-I°. Degree of TR remained unchanged through 6 months after PVI. Furthermore, moderate to severe TR was an independent predictor for AF recurrence after PVI (hazard ratio, 1.99 [95% confidence interval, 1.09–3.63]; p=0.01).