Improved procedural workflow for catheter ablation of paroxysmal AF with high density mapping system and advanced technology: insights from a multicenter, international study
Authors: Segreti L , Solimene F , Ramos Maqueda J , De Sanctis V , Porta Sanchez A , Rossi P , Maggio R , Alvarez Lopez M , Valles Gras E , Malacrida M , Garcia-Bolao I 
Published: May 2024

Abstract

Background
A high incidence of pulmonary vein (PV) reconnection has been reported in patients with clinical recurrences of AF. Low-voltage activity beyond PVs (e.g. antral activity potentials, RAP) likely represent vulnerabilities in antral lesion sets and they may contribute to ablation failures.

Purpose
The aim of this study is to validate a structured application of an approach that includes the complete abolition of any antral potential achieving electrical quiescence in antral regions.

Methods
DELETE AF is a prospective, single-arm, international post-market cohort study. Consecutive patients from 10 centers who were undergoing radiofrequency ablation of paroxysmal AF were included. The Lumipoint map-analysis tool was used sequentially on each PV component. Post-ablation, all patients were monitored with ambulatory event monitoring, starting within 30 days post-ablation to proactively detect and manage any recurrences within the 90-day blanking period, as well as Holter monitoring at 3, 6, 9, and 12 months post-ablation. Additional ECG monitoring were performed as indicated by patient symptoms. The ablation endpoint was PV isolation (PVI). Long-term outcome was the recurrence of AF over follow-up. Data are reported as median [IQ range].

Results
One-hundred ten cases of AF ablation were analyzed: 28 (25.5%) females, age=63[56-69] years, 24 (21.8%) patients with a history of AT/AFL. The procedure duration was 58[24-76] min (RF delivery time=18[12-28] min, number of ablation spots=77[44-101]) and the fluoroscopy time was 13[9-19] min. Thirty-eight (34.5%) were repeat ablation: in these patients after initial mapping a total of 114 PV gaps (PVGs) in 29 (76.3%) patients and 69 RAPs in 15 patients (39.5%) were found. After ablation, a total of 5 early PVGs in 2 (1.8%) patients (all in de novo procedures) and a total of 10 RAPs in 7 (6.3%) patients (3 out 38 -7.9%- of repeat ablations vs 4 out 72 -5.6%- of de novo cases, p=0.690) were detected after first remapping. Each residual PVG was first targeted and additional focal ablations were performed at any low-voltage propagation suspected within the region of previous antral ablation. Acute procedural success was 100%, with all PVs successfully isolated and RAPs completely abolished in all study patients except for one that still exhibited a residual low-voltage antral signal after adenosine infusion with no PV conduction. Eighty-six (78.2%) patients had complete follow-up information. During the 90-day blanking period, 8 (9.2%) patients experienced an early recurrence. After the blanking period, over a follow-up of 357[190-380] days, 13 patients (15.1%) suffered an AF recurrence (time to recurrence: 207[144-300] days). No major complications or adverse events occurred.

Conclusion
A structured ablation workflow for catheter ablation, with consistent high-density mapping and improved diagnostic tools to guide the ablation, proved to be safe and effective in paroxysmal AF.