Abstract 4368714: Post Index Atrial Fibrillation Ablation Recurrences Over 5 Years: Impact of Ablation Targets Beyond Pulmonary Vein Antra

Background: Pulmonary vein isolation (PVI) is the cornerstone of atrial fibrillation (AF) ablation. Adjunctive ablation beyond PVI, esp. posterior wall (PW) ablation, has been widely adopted with the introduction of pulsed-field ablation. We sought to compare AF/atrial flutter (AFL) recurrence outcomes following PVI-plus approaches versus PVI-alone. Methods: We retrospectively analyzed all first-time AF ablations between 2008-2022 at our center. AF/AFL recurrence was defined as any clinically documented AF/AFL after a 3-month blanking period. All patients underwent PVI; those who received additional ablation lesions other than cavotricuspid isthmus (CTI) ablation for AFL were classified as PVI-plus, and the remainder as PVI-alone. Time-to-recurrence was analyzed using Kaplan-Meier (KM) curves and Cox proportional hazards (adjusted for baseline variables) with outcomes censored at 5 years. Results: 2,906 patients (age 62.9±10.5 years; 30.5% female; 49.4% paroxysmal AF) underwent first-time AF ablation. PVI-plus was performed in 993 patients (34.2%). CTI AFL was ablated in 1,220 (42.0%). Over a follow-up of 6.0±4.3 years, 1,503 patients (51.7%) had AF/AFL recurrence. PVI-plus ablation was more common among those with recurrence (36.6% vs 31.6%, p=0.005). In unadjusted analysis, both PVI-plus and PW ablation were associated with higher AF/AFL recurrence compared to PVI-alone [HR 1.20 (1.07–1.34), p=0.002 and HR 1.25 (1.06–1.47), p=0.01, respectively]. However, after adjusting for baseline variables, neither was different from PVI-alone [HR for PVI-plus: 1.05 (0.93–1.18), p=0.5; HR for PW ablation: 0.97 (0.81–1.16), p=0.7]. CTI flutter line was not associated with recurrence in unadjusted analysis [HR 0.97 (0.87–1.08), p=0.5], but was linked to lower recurrence after adjustment for confounders [HR 0.87 (0.78–0.98), p=0.02]. In KM analysis stratified by AF type, PVI-plus and PW ablations showed similar recurrence incidence compared to PVI-alone in both paroxysmal and persistent AF (p>0.05 for both). However, CTI flutter line was associated with a lower recurrence in persistent AF (p=0.01), but not in paroxysmal AF (p=0.7). Conclusion: PVI-plus ablation, including PW ablation, was not associated with any difference in AF/AFL recurrence in either paroxysmal or persistent AF. In contrast, CTI flutter ablation reduced recurrences in those with persistent AF. This may suggest a role for empiric CTI ablation in persistent AF.