Atrial fibrillation is the most common arrhythmia in the population and is often caused by arrhythmogenic foci located in the pulmonary veins. For this reason, the first attempt in atrial fibrillation catheter ablation procedures is to isolate these structures (the procedure is called indeed "pulmonary vein isolation"), which results in abolishment of arrhythmia recurrence in up to 85% of patients at short and mid-term follow-up. However, a subset of patients experience an atrial tachyarrhytmia recurrence and a second catheter ablation procedure has to be performed. If pulmary vein isolation is proven to be durable, other arrhythmogenic foci could be implicated in arrhythmia recurrence. Among extra-pulmonary vein foci, superior vena cava has been described as the most frequently involved in atrial fibrillation initiation. Therefore, its ablation could result in improved freedom from atrial fibrillation episodes during follow-up. In the present study, we sought to evaluate the safety and effectiveness of empirical superior vena cava isolation in terms of arrhythmia-free survival in patients with paroxysmal atrial fibrillation recurrence despite durable pulmonary vein isolation.