PLS as AF substrate
LGE-MRI based computer simulation model demonstrated that meandering re-entrant AF driver was localized in boundary zones between fibrotic and non-fibrotic tissue characterized with high fibrosis density and entropy where the lower local conduction velocity was documented.20,22Furthermore, they has demonstrated that the residual fibrosis after catheter ablation might be attributable to preserved re-entrant drivers and the emergence of new re-entrant driver.23 This strongly indicated that the all fibrosis with high density and entropy were possible ablation targets. Therefore, the RF application at the PLS was continued, even in cases where AF termination was achieved during the procedure. Recently, Boyle et al. had presented the computationally guided personalized targeted ablation as a proof-of -concept feasibility study.7 Furthermore, they suggested that LGE-MRI based computationally guided ablation could provide not only accurate prediction of AF ablation targets but could overcome the prolonged procedure time and higher radiation exposure due to the difficulty of a conventional mapping of atrial electrical activity. In our study, both procedure time and fluoroscopy time ware acceptable as compared to that of conventional ablation procedure, because additional target site was predefined by the preprocedural LGE-MRI and no further mapping was necessary during the procedure. We would hope that the PLS ablation could improve the rhythm outcome in persistent AF patients without increasing of the procedure time and radiation exposure.