Abstract
AIMS: The superior vena cava (SVC) has been implicated as a non-pulmonary vein trigger in the initiation and maintenance of atrial fibrillation (AF). However, the incremental benefit of empiric SVC isolation (SVCI) in addition to pulmonary vein isolation (PVI) for paroxysmal AF (PAF) remains inconclusive. This study aimed to determine whether adding empiric SVCI to PVI improves freedom from atrial arrhythmia (ATA) recurrence in patients with PAF. METHODS AND RESULTS: A total of 302 patients with PAF, aged 18-75 years, undergoing index ablation, were enrolled and randomized in a 1:1 ratio to either the PVI plus SVCI group or the PVI alone group between May 2021 and February 2024. In the PVI plus SVCI group, PVI was performed first, followed by empiric SVCI. In the PVI alone group, only PVI was performed. Among 302 randomized patients [median (IQR) age, 64.9 (56.0-70.0) years, 165 men (54.6%)], 302 (100%) completed the 3-month blanking period and contributed to the efficacy analysis. After a median follow-up of 20 months, the recurrence of rate of ATAs did not differ significantly between the PVI plus SVCI group (20/151 patients, 13.2%) and PVI alone group (29/151, 19.2%) without taking antiarrhythmic drugs (hazard ratio, 0.68, 95% confidence interval 0.38-1.20, P = 0.182). Subgroup outcomes analysis further demonstrated no significant interaction across subgroups. CONCLUSION: Among patients with PAF undergoing initial ablation, the addition of empiric SVCI to PVI, compared with PVI alone, did not significantly improve freedom from ATA recurrence. CLINICAL TRIAL REGISTRATION: This study was registered with Chinese Clinical Trials Registry: ChiCTR220005554.