Ectopic potentials in the SVC can act not only as a trigger but also as a driver of AF. These potentials may be refractory to conventional pulmonary vein isolation for AF. In the present case, the atrium resumed a sinus rhythm spontaneously on the completion of SVC isolation and AF could no longer be induced. However, there was residual fibrillatory activity in the SVC. These findings suggest that residual activity in the SVC worked as a driver of AF. SVC reconnection is commonly reported, with a prevalence of 70%. Thus, we decided to eliminate residual fibrillatory activity in the SVC to prevent recurrence of AF after the third catheter ablation session. In the presence of a fibrillatory pattern, conventional activation mapping techniques cannot map residual SVC activity; however, ICL mapping using the CARTO system can identify the target site of ablation in the isolated SVC.