Initial experiences on acute efficacy and safety of pulmonary vein isolation and left atrial roof ablation in patients with atrial fibrillation using a novel pulsed field ablation loop catheter

INTRODUCTION

Pulsed field ablation (PFA) is a novel nonthermal energy source for ablation of atrial fibrillation (AF). Various PFA ablation systems are currently being developed. Recently, a novel CE-approved PFA single-shot loop catheter (PulseSelect™ PFA System, Medtronic) was introduced. Data on this commercially available system is sparse. We sought to assess the feasibility, safety, and acute efficacy of pulmonary vein isolation (PVI) and additional left atrial roof ablation (LARA) with this novel ablation system.

METHODS

Consecutive paroxysmal and persistent AF patients who underwent first-time PFA ablation using the PFA loop catheter from April 2024 to May 2024 were enrolled. Additional LARA was only performed in patients with persistent AF and left atrial enlargement (LA area > 20cm2). All procedures were performed under general anesthesia or deep analgo-sedation.

RESULTS 

In total, 39 AF patients were included in the study (33.3 % female, mean age 65 ± 11 years, BMI 29.1 ± 4.0 kg/m2, 46.2 % persistent AF). Mean CHA2DS2-VASc score was 2.2 ± 1.5. Mean left atrial (LA) area and left ventricular ejection fraction were 23.0 ± 5.5 cm2 and 57 ± 5 %. Mean duration since first AF diagnosis was 3.1 ± 4.9 years. Out of 39 patients 12 (30.8 %) patients were treated with adjunctive LARA. Two additional cavotricuspid isthmus (CTI) ablations (5.1 %) using PFA was performed due to typical atrial flutter. 

Skin-to-skin procedural time was 82.0 ± 15.6 min. Fluoroscopy time and dose area product were 14.1 ± 4.8min and 6.7 ± 3.7 Gycm2, respectively. Time of PFA catheter in LA was 57.8 ± 12.1 min. Acute PVI was achieved in 100 % of pulmonary veins (PVs). Total number of PV applications was 35.5 ± 3.2. Mean number of applications in left PVs and right PVs were 18.1 ± 2.4 and 17.4 ± 1.5, respectively (Table 1). LARA was successfully performed with 7.3 ± 2.3 applications. Conduction block across LA roof was confirmed in all 12 (100 %) patients. Adjunctive LA posterior wall isolation was performed in one patient with 12 applications. Ablation of CTI was performed with 9 ± 4 applications and afterwards bidirectional blockade was confirmed in all patients (100%). One vascular access complication (hematoma) was observed (2,6 %). No other complications occurred. 

CONCLUSION

This study demonstrates feasibility, safety, and acute efficacy of pulmonary vein isolation and additional LARA using this novel PFA loop catheter. The system can easily be integrated with standard PVI workflows. Further and larger studies are warranted to assess the clinical long-term effectiveness and safety of this PFA system.