Is focal pulsed-field ablation feasible and effective for treating right atrial tachycardia?
Focal pulsed-field ablation for right atrial tachycardia appears feasible and acutely effective, with a low risk of permanent phrenic nerve injury.
Abstract Background Radiofrequency (RF) ablation of focal right-atrial tachycardia (RAT) near the phrenic nerve carries a risk of permanent damage to both phrenic nerve and sinus node. Pulsed-field ablation (PFA) uses primarily nonthermal, relatively myocardium-selective electroporation and may mitigate this risk. We report the largest series to date of focal PFA for RAT. Methods We retrospectively analyzed 16 consecutive patients (9 women, mean age 61 ± 13 years) who underwent focal PFA for RAT between November 2023 and May 2025 at a single center. Patients had preserved left-ventricular function; hypertension (63 %) and dyslipidemia (81 %) were common. Three had failed prior RF ablation. The arrhythmia was induced with pacing or pharmacologic stimulation and mapped with high-density multipolar or halo catheters; sinus-node and phrenic-nerve locations were delineated when the focus lay nearby. Point-by-point PFA using the CENTAURI™ System was delivered via a contact-force catheter at 25 Ampere, reduced to 22 Ampere when ablating sites with phrenic capture. Acute success was defined as non-inducibility after a 30-minute waiting period. Results Half of the tachycardias originated from the crista terminalis, predominantly from the mid and inferior segments. Two cases arose from the anterior and two from the posterior inferolateral right atrium, two from the anterior superolateral region, one from the posterior superior-septal right atrium, and one from the inferoseptal tricuspid isthmus near the coronary sinus ostium. Mean procedure time was 174 ± 60 min. Additional PFA lesions for concomitant atrial fibrillation (superior vena cava isolation with or without linear lines) were delivered in three patients. Acute termination with non-inducibility was achieved in all. Two patients had transient phrenic-nerve palsy and one transient ST-segment elevation due to coronary spasm when ablating near the coronary sinus ostium; all resolved without sequelae. No other complications were observed. Nine patients had follow-up Holter monitoring (after a mean of 4.9 ± 2.4 months); one of these patients had recurrence during follow-up. Conclusion In this early single-centre experience, focal PFA for RAT was feasible, acutely effective and associated with a low complication rate. The selective nature of PFA seems to minimize permanent phrenic nerve injury.
Keelani et al. (Mon,) studied this question.