Feasibility and Clinical Efficacy of Focal Pulsed Field Ablation in Patients With Non-Pulmonary Vein Triggered Atrial Arrhythmia From the Superior Caval Vein.

Introduction: In patients with atrial arrhythmias originating from the superior vena cava (SVC), the use of radiofrequency energy to isolate the SVC is associated with a significant risk of injury both to the phrenic nerve and the sinus node. Pulsed field ablation (PFA) may overcome the disadvantages of thermal energy and improve both ablation efficacy and safety.

Objective: We report the feasibility, safety, and clinical efficacy of focal monopolar PFA in patients with the origin of their atrial arrhythmia in the SVC.

Methods: Nine patients (7 men, age 66 ± 8 years) with SVC-induced paroxysmal AF (n = 3), persistent AF (n = 5), or frequent premature atrial beats (n = 1) underwent SVC isolation using focal monopolar PFA.

Results: Acute circumferential SVC isolation was achieved in all cases, using 22 Ampere (A) or 25 A in areas with or without phrenic capture, respectively. The safety profile was excellent: two patients had transient sinus arrest and two had transient phrenic nerve stunning. Sinus node and phrenic nerve function recovered during the procedure, and no permanent damage was observed at follow-up. Coronary vasospasm occurred (and quickly resolved after injection of nitroglycerin) in one patient during additional ablation of a focal atrial tachycardia at the coronary sinus ostium. Kidney function remained stable before and after ablation in all patients.

Conclusions: In this patient cohort with SVC-triggered atrial arrhythmia, isolation using focal monopolar PFA was feasible, effective, and safe. No permanent injury to the phrenic nerve or sinus node was observed.