Abstract 15934: Comparison of Atrial Fibrillation Burden Reduction in Patients With Paroxysmal and Persistent Atrial Fibrillation Undergoing Cryoballoon Pulmonary Vein Isolation

Abstract

Background: Pulmonary vein isolation (PVI) is a cornerstone of atrial fibrillation (AF) ablation procedures to treat symptomatic AF. Ablation success is defined by absence of AF recurrence >30 seconds. However, reduction in AF burden (AFB) is also an important endpoint. Whether patients with paroxysmal (PAF) and persistent AF (PeAF) have similar reduction in AFB post-ablation is unknown. Objective: To compare the decrease in AFB following cryoballoon (CB) PVI in patients with PAF and PeAF. Methods: We enrolled consecutive pts with an implantable loop recorder (ILR) who subsequently underwent CB PVI. All patients were followed prospectively for at least one year, or until repeat ablation; we compared AFB pre and post-ablation. Results: The cohort included had 47 patients (66 ± 10 years; 32 [68%] male; PAF [n=23, 49%]; CHA 2 DS 2 -VASc 2.7 ± 1.7, 34 [72%] on AAD at the time of ablation). A median of 136 days [IQR 280, 73; minimum of 30 days] of ILR data pre-ablation were available. The median AFB for PAF was 4.7% [IQR 0.9, 14.8] and PeAF was 6.8% [IQR 1.1, 40.4]. After excluding a 3-month post-ablation blanking period, recurrent AF occurred in 12 (52%) PAF and 11 (46%) PeAF patients. The median AFB post-ablation for PAF and PeAF cohorts was 0.03%, [IQR 0, 0.3] and 0.04%, [IQR 0, 1.1], respectively. This represents a >99% reduction in AFB. Conclusion: Although 50% of patients undergoing CB PVI for PAF or PeAF had a recurrence of AF, there was >99% reduction in AFB in both groups. These data highlight the importance of using AFB burden as a marker of therapeutic efficacy post-AF ablation.