Predictors of first-pass isolation in patients with recurrent atrial fibrillation: A retrospective cohort study.

Background: Pulmonary vein isolation (PVI) is superior to antiarrhythmics for the management of atrial fibrillation, but repeat ablation is often required for durable rhythm control. Factors influencing first-pass isolation (FPI) and whether FPI predicts durable isolation are not well known. Objective: The study sought to determine factors associated with FPI and rates of chronic reconnection among those with and without FPI at index PVI in patients undergoing repeat ablation. Methods: We retrospectively identified 483 patients at our institution who underwent first-time PVI in 2021. Of these, 63 who had repeat ablation between 2021 and 2023 were included in the study. Logistic regression was used for statistical analysis for predictors of FPI during index PVI. Results: The mean age was 65 years, 67% of patients were male, 90% were White, and 73% had persistent atrial fibrillation. At index PVI, FPI was achieved in 58% of left pulmonary veins (PVs), 48% of right PVs, and 25% of posterior wall isolations. Bilateral FPI was achieved in 35% of patients. At redo PVI, the right superior PV (47%) was most frequently reconnected. Lack of PFI of the right PVs at index PVI was associated with a 14-fold risk of chronic reconnection. Elevated left atrial voltage predicted the absence of FPI of the right PVs but not the left PVs. Conclusion: Increased left atrial voltage predicts a lack of FPI in the right PVs but not in the left PVs. Lack of FPI of right PVs predicts chronic reconnection.