Real-world comparison of variable vs fixed-loop circular pulsed field ablation catheters: Acute outcomes including non-pulmonary vein ablation.

Background: Pulsed field ablation (PFA) is an emerging non-thermal approach for pulmonary vein isolation (PVI) in atrial fibrillation (AF). Comparative real-world data between variable-loop circular catheter (VLCC; VARIPULSE™, Biosense Webster, Inc) and fixed-loop circular catheter (FLCC; PulseSelect™, Medtronic) catheters, including non-PVI ablation, are limited. Objective: To compare acute efficacy, procedural characteristics, and safety of PVI, and adjunctive ablations performed with VLCC vs FLCC during clinical implementation. Methods: Overall, 90 consecutive patients were studied (first 45 VLCC and 45 FLCC cases). FLCC procedures used fluoroscopic guidance; VLCC was integrated with 3-dimensional mapping, reflecting standard real-world use of each catheter. Additional ablations were performed at the operator's discretion. Acute outcomes and complications were analyzed. Results: Acute PVI success was 100% in both groups. Additional ablations (cavotricuspid isthmus [CTI], roof lines, posterior wall, superior vena cava [SVC]) were performed in 17 (VLCC) and 15 (FLCC) patients, achieving bidirectional block without Radiofrequency touch-ups. In PVI-only cases, FLCC was associated with shorter median procedure time (67.2 vs 76 min, P < .001), whereas VLCC had reduced fluoroscopy time (8.3 vs 11.4 min, P < .001). Major complication rates were low and comparable (2.2% vs 0%, P = 1). Conclusion: This first clinical comparison demonstrated high acute efficacy and favorable safety profiles, with notable procedural differences reflecting their distinct workflows of 2 circular PFA catheter systems for AF ablation. Likewise, this includes the first reported successful CTI, SVC and mitral isthmus ablation using VLCC reflecting its versatility for ablation. Further research is warranted to assess long-term outcomes and lesion durability.