INTRODUCTION
While pulmonary vein isolation (PVI) is associated with high success
rates in patients with paroxysmal atrial fibrillation
(PAF),1-4 ablation outcomes in patients with
persistent AF (PsAF) are more modest. In patients with PsAF, additional
ablation strategies targeting AF substrate demonstrated improved
clinical outcomes5. Linear ablation including roof and
mitral isthmus (MI) lines6 and electrogram
(EGM)-guided ablation7,8 techniques have been widely
used in this context. However, the reported outcomes following ablation
with these techniques have been variable.9,10 In a
previous multicenter randomized trial, additional AF substrate ablation
(roof and MI lines or complex fractionated atrial electrogram [CFAE]
or EGM-guided) beyond PVI for PsAF was not associated with incremental
benefit compared to PVI alone. Importantly, while AF/atrial tachycardia
(AT)-free survival rates were relatively low (around 40%), operator
bias for linear ablation and CFAE-guided ablation should be
considered.11 There is a paucity of data on the
relative efficacy of linear ablation and CFAE or EGM-guided ablation for
PsAF.11,12 In the present study we compared very
long-term clinical outcomes of linear ablation and EGM-guided
ablation.