Short-term outcomes during the blanking period after catheter ablation using a novel circular pulsed field ablation system in patients with atrial fibrillation

A novel CE-approved circular array pulsed field ablation (PFA) catheter (PulseSelect™ PFA System) has recently been introduced. However, data on the follow-up outcomes of this commercially available system remain limited. The aim of this study was to evaluate arrhythmia recurrences and safety during the 3-month blanking period after pulmonary vein isolation (PVI), additional left atrial roof ablation (LARA), and cavo-tricuspid isthmus (CTI) ablation using this novel system.

Consecutive patients with paroxysmal or persistent atrial fibrillation (AF) who underwent first-time ablation with the PFA loop catheter between April and July 2024 were enrolled. Follow-up assessments, conducted 90 days after the procedure or in response to symptoms, included screenings for adverse events and recurrent atrial arrhythmias lasting more than 30 seconds, as detected by 12-lead ECGs and 24-hour Holter monitoring.

A total of 50 AF patients were included in the study (32% female, mean age 64 ± 11 years, BMI 29.1 ± 3.9 kg/m², 56% persistent AF). Of these, 14 patients (21%) underwent adjunctive LARA for persistent AF with a left atrial area >20 cm², while 2 patients (4%) received additional CTI ablation for typical atrial flutter. Acute PVI was achieved in 100% of pulmonary veins, and conduction block across the LA roof and CTI was confirmed in all patients.

After a mean follow-up of 3.2 ± 0.6 months (median: 3.2), recurrent atrial arrhythmias were documented in 9 patients (18%): 6/34 (18%) in the PVI-only group, 2/14 (14%) in the PVI + LARA group, and 1/2 in the PVI + CTI group (p = 0.517). Eight of the nine recurrences were AF, with one case of typical atrial flutter. One patient in the PVI + CTI group required a repeat CTI ablation. Recurrences were distributed as follows: 5 in the first month, 2 in the second month, and 2 in the third month of the blanking period. In the univariate (logistic regression) analysis, no significant predictors of arrhythmia recurrence were identified. No major adverse events were observed during the hospital stay or the follow-up period.

This study demonstrates a favorable short-term outcome during the 3-month blanking period following catheter ablation with the novel circular PFA catheter. Further larger-scale studies are necessary to evaluate the long-term clinical efficacy and safety of this system in patients with atrial fibrillation and flutter.