A multicenter evaluation of repeat ablation for atrial fibrillation in patients with isolated pulmonary veins: a Netherlands Heart Registration study
Authors: Magni F T , Samuels M , Van Der Stoel M , Hassink R J , Trines S A I , Kemme M J B , Balt J C , Van Der Voort P H , Luermans J G L , De Jong J S S , Blaauw Y 
Published: May 2024

Abstract

Background
Of the 25-50% atrial fibrillation (AF) ablation patients who undergo repeat ablation, approximately 15-30% have all pulmonary veins (PVs) isolated at the repeat procedure. Currently, there is limited evidence and a lack of consensus on the appropriate treatment strategy for patients with isolated PVs.

Purpose
Our aim was to characterize and compare the effectiveness of repeat AF ablation strategies to reduce AF recurrences in patients with isolated PVs using a real-world multicenter registry.

Methods
All AF patients referred for repeat AF ablation with all PVs isolated at 8 hospitals in the Netherlands were included (Netherlands Heart Registration; 2016-2019). Medical record reviews were conducted for all patients referred for repeat AF ablation to determine study eligibility, the presence of PV reconnection, ablation strategy used, and the outcome of AF recurrence. Patients referred for repeat AF ablation, with PVI only conducted during previous ablations, and all PVs isolated were eligible. Effectiveness of repeat AF ablation strategies were assessed with multivariable Cox models comparing individual ablation strategies, number of ablation strategies performed, and presence of persistent AF.

Results
Of 2,311 repeat AF ablations performed, 274 (11.9%) were eligible and had all PVs isolated (Figure 1). Patients with isolated PVs were a median age of 66 (IQR 58-70) years, 44.2% were women, 45.6% had persistent or long-standing persistent AF, and the median CHA2DS2-Vasc score was 2 (IQR 1-3). Ablation was not performed in 33 (12.0%) patients with isolated PVs (Figure 2a). A single ablation strategy was performed most often (41.2%; Figure 2a). Posterior box ablation was the most frequent (58.4%) ablation strategy performed, followed by antralization of the PVs (26.3%). Over a median follow-up of 2.0 (1.0-3.3) years, 147 (59.8%) patients with isolated PVs had an AF recurrence &gt;3 months after repeat ablation and 30 (12.7%) patients had another repeat AF ablation within 1 year of repeat procedure. After multivariable adjustment, no difference in AF recurrences was detected between ablation strategies [p&gt;0.05 for all; Figure 2b]. Further, there was no difference detected in AF recurrences for the number of ablation strategies performed (Figure 2c), the individual ablation strategy conducted, and persistent AF (p&gt;0.05 for all). Among patients with isolated PVs, patients with larger left atrial size had a higher risk of AF recurrences [adjusted HR 1.03 (95% CI 1.01-1.05)].

Conclusion
Among the 2,311 repeat AF ablations performed, 11.9% had all PVs isolated. Despite multiple ablation strategies performed for isolated PVs, 59.8% of patients had an AF recurrence over follow-up and no difference in the incidence of AF recurrences was detected between repeat ablation strategies. Further evidence is warranted to determine an effective treatment strategy to reduce AF recurrences in AF patients with isolated PVs.