Abstract Body (Do not enter title and authors here): Background: Pulsed field ablation (PFA) has emerged as a safe and effective alternative to thermal ablation modalities for treatment of paroxysmal and persistent AF in a de novo procedure.
Research Questions: Since the FaraPulse system (Boston Scientific) was approved by FDA, no data was reported on whether PFA can be used in redo procedures.
Aims: We reported our initial experience with PFA in patients with recurrent atrial tachyarrhythmias (ATs) who failed at least one thermal ablation of AF.
Methods: Consecutive patients receiving redo ablation using PFA (FaraPulse) for recurrent ATs were enrolled. ICE and fluoroscopy were used to guide the placement of FaraWave catheter. Voltage and activation mapping of LA were performed in all patients before ablation using Orion high density mapping catheter and Rhythmia system. Ablation strategy included PV re-isolation as needed, LA posterior wall (PW) isolation if low voltage zone was identified, and ablation of any organized ATs. Procedural endpoints were PVs and LAPW isolation, non-inducibility for ATs and bidirectional block for linear ablation.
Results: 15 patients (12 male; age 66.3±10.3 years) were included. The median number of prior RF ablations was 2; 2 patients also received one cryoballoon ablation. Patients presented with persistent (80%) AF or paroxysmal (20%) AF with/without documented organized ATs. By using PFA, LAPW isolation was performed and achieved in all patients, while 11 (73.3%) patients required reisolation of at least one PV (Figure). Organized ATs were present/induced in 7 (46.7%) patients including 3 peri-mitral AFL, 3 LA roof-dependent AFL, 3 CTI AFL and 3 atrial tachycardias from LA roof, LA septum and RA roof respectively. RF ablation was required in 2 patients (2/7, 28.5%) to eliminate CTI AFL. Per case total PFA applications number were 48.7±24.4 (46, 22-90); total fluoroscopy time was 6.8±5.6 mins. No major peri-procedural complication was observed except for one case (90 PFA applications) of hemolysis and acute renal failure that completely recovered.
Conclusion: PFA of recurrent ATs after failed thermal ablation is feasible and safe acutely if limited the applications. The long-term outcome of this strategy warrants further investigation.