Pacing inducibility from the SVC
We performed rapid electrical stimulation from the SVC to induce AF based on previously published research 13, but the induction rate was much higher (36% in our study vs. 19% in a previous study). The possible reason was that in the previous study, they only paced at one point in the SVC and did not investigate the SVC-ERP, whereas we investigated the three portions of the SVC and performed burst pacing from the shortest SVC-ERP. Therefore, the induction rate in the present study was considered to be high.