A)The longitudinal linear ablation in a cranial direction was performed with the mapping catheter positioned in the superior vena cava (SVC), pacing the phrenic nerve (PN) for confirming compound muscle action potential. B) SVC isolation was performed during the PN pacing with 1200-ms interval. The intracardiac electrogram shows SVC isolation from the 3^rd beat.

Supplement 1 The activation map during sinus rhythm shows the reconduction between the superior vena cava (SVC) and right atrium (RA) using Coherent map^TM in CARTO 3 system.