Study population
We retrospectively analyzed 286 patients who underwent AF ablation in our hospital from January 2016 to June 2018. Among the 286 patients, we included 36 patients in this study. In those patients, a Force-Time Integral (FTI) guided SVCI was performed for patients whose length of the SVC sleeve was more than 3cm, and who revealed premature atrial contraction from the SVC. The patient characteristics are shown in Table 1. The study protocol was approved by the hospital’s institutional review board(02-007).