Feasibility and safety of CTI pulsed-field ablation during PVI in routine practice

Background

Atrial flutter (AFL) and atrial fibrillation (AF) frequently co-exist and may potentiate one another. Cavotricuspid isthmus (CTI) ablation is the treatment of choice for typical CTI-dependent AFL, whereas pulmonary vein isolation (PVI) is the gold-standard catheter-based therapy for AF. Although pulsed-field ablation (PFA) has been widely adopted for PVI in recent years, CTI ablation with PFA remains off-label and supported by limited real-world evidence. We aimed to evaluate the feasibility, efficacy, and periprocedural safety of CTI ablation using PFA in patients undergoing combined PVI and CTI ablation.

Methods

Single-center retrospective study including consecutive patients referred for PVI with PFA who underwent concomitant CTI ablation between 2022 and 2025. CTI ablation was performed using either PFA or radiofrequency (RF) catheters from commercially available systems, according to operator preference. Acute success was defined as complete bidirectional CTI block, confirmed by differential pacing after a waiting period. Procedural characteristics and periprocedural complications were recorded. The primary outcome was defined as recurrence of typical AFL documented on 12-lead ECG, Holter monitoring, or clinical records. Recurrence of any sustained atrial tachyarrhythmia was the secondary outcome.

Results

A total of 65 patients were included (68% male; mean age 66.8 ± 11.2 years). Redo procedures accounted for 12% of cases for PVI and 3% for CTI. Typical AFL had been previously documented in 71% of patients, while the remaining 29% had CTI-dependent AFL induced during the index PVI procedure. Concomitant CTI ablation was performed using PFA in 50 procedures (77%) and RF in 15 (23%). Within the PFA group, the systems used were FARAPULSE (62%), VARIPULSE (14%), Volt (14%), Affera (8%) and CENTAURI (2%). Acute bidirectional CTI block was achieved in all cases. No periprocedural adverse events, including cardiac tamponade, coronary/other vascular complications, stroke/transient ischaemic attack or procedure-related death were documented. Routine post-procedural monitoring did not reveal delayed ischemic ECG changes or clinically relevant coronary events.

Over a median follow-up of 8 months (IQR 4–12), typical AFL recurred in 1 patient (2%) in the PFA group and none (0/15) in the RF group. The secondary outcome occurred in 2 patients (4%) in the PFA group and 3 patients (20%) in the RF group (p=0.130).

Conclusion

In this real-world cohort undergoing combined PVI and CTI ablation, CTI-PFA achieved 100% acute bidirectional block without any significant periprocedural complication. Mid-term recurrence of typical AFL was rare and comparable to RF-based CTI ablation. These findings support prospective controlled studies to confirm lesion durability and clarify the role of CTI-PFA in integrated AF ablation strategies.Figure 1.