Effectiveness of a Standardized Approach to Repeat Paroxysmal Atrial Fibrillation Ablation: Insights Into the Value of Extrapulmonary Vein Targets.

Background: The optimal approach to repeat catheter ablation for recurrent paroxysmal atrial fibrillation (PAF) is unknown.

Methods: Consecutive patients undergoing repeat PAF ablation were studied. The following 6-step approach was used in all cases: re-isolation of reconnected pulmonary veins (PVs); ablation of left atrial low-voltage areas (LVAs); targeted ablation of clinical or inducible atrial flutter/tachycardia; non-PV trigger ablation; ablation of inducible supraventricular tachycardia; and additional empirical ablation based on operator judgement. The primary study outcome was atrial arrhythmia-free survival at 1 year.

Results: One hundred thirteen patients were included in the study (mean age 63.7 ± 8.6 years, 28.3% women). In this cohort, 73.5% had PV reconnection(s), 31.9% had LVAs, 10.6% had identifiable non-PV triggers, 5.3% had inducible atrioventricular nodal re-entrant tachycardia, 31.9% underwent atrial flutter/tachycardia ablation, and 12.4% had additional empirical ablation performed. Arrhythmia-free survival at 1 year was 53.1%. Patients with arrhythmia recurrence were more likely to be older, female, have hypertension, have durably isolated PVs, and to have undergone LVA ablation. In multivariable analysis, female sex and LVA ablation remained predictive of arrhythmia recurrence. Among patients with durably isolated PVs, only female sex was (negatively) associated with procedural success.

Conclusions: A comprehensive protocol for repeat PAF ablation resulted in arrhythmia-free survival at 1 year in 53% of patients. Durably isolated PVs were observed in 26.5% of cases. None of the ablation protocol's steps was suggested to independently improve procedural success. Further research to determine the optimal ablation strategy in patients undergoing repeat ablation for PAF is needed, a growing proportion of whom are expected to have durably isolated PVs.