Patient population
A total of 31 consecutive persistent AF patients with patchy LGE site were enrolled in this study (PLS group). The chronic kidney disease patients were excluded from this study, because no LGE-MRI could be performed before ablation. As a control group, propensity matched 62 patients with or without the patchy LGE site were selected from Kobe University AF registry including a total 241 persistent AF patients who underwent conventional catheter ablation (31 in the control group with the patchy LGE site, 31 in the control group without the patchy LGE site). The study design and flowchart were shown in Figure 1. The study was approved by the local ethics committee and complied with the Declaration of Helsinki (Committee of 2020.7.21., Approval No. B200121).