Evaluation of a new approach for persistent atrial fibrillation: Ablation index-guided pulmonary veins isolation with contiguous lesions

Abstract

Pulmonary veins isolation (PVI) may be an appropriate ablation strategy for persistent atrial fibrillation (peAF) treatment. We aimed to evaluate in a peAF population 1 year-outcome and safety of a new PVI approach based on delivery of deep and closely spaced radiofrequency (RF) lesions. Outpatient pharmacological or electrical cardioversion (ECV) was intended prior to ablation in 53 peAF patients (pts). On the day of ablation, 30 peAF pts who were either in sinus rhythm (SR) or exhibited typical atrial flutter (AFL) were included in this prospective study. Ablation index (AI)-guided PVI was performed targeting interlesion distance ≤ 6 mm and AI ≥ 550 arbitrary unit (au) at anterior wall, ≥ 400 au at posterior wall and roof (≥ 300 au at vicinity of esophagus). CTI ablation was performed only in case of AFL. Recurrence was defined as any AF, atrial tachycardia (AT) or AFL (AF/AT/AFL ˃ 30s) either on Holter electrocardiographs or by cardiac devices monitoring at 3, 6 and 12 months. ECV was performed in 26 (87%) of pts (64 ± 9 years, 80% male), 51 ± 42 days prior to ablation. Three pts (10%) had long-standing peAF. LA anteroposterior diameter was 45 ± 7 mm. PVI was achieved in all pts and CTI ablation performed in 6. Mean procedure time, RF time and fluoroscopy time were respectively 156 ± 25 min, 26 ± 6 min and 4 ± 4 min. At a median follow-up of 15 ± 4 months, 24/30 pts (80%) were free from AF/AT/AFL after a single procedure, with 8 pts (27%) still on antiarrhythmic drugs. Out of 6 recurrences, 5 were paroxysmal form. No periprocedural complications occurred. After a single procedure and midterm follow-up, Ablation index-guided PVI is efficient in maintaining sinus rhythm in peAF pts who exhibit, on the day of ablation, either sinus rhythm or typical AFL. Randomized studies with larger scale and longer follow-up are required.