Electrophysiological characteristics of atrial tachycardia after pulmonary vein isolation of atrial fibrillation.

Pulmonary vein (PV) isolation is a cornerstone of atrial fibrillation (AF) ablation. This technique is now widely spread all over the world. Numerous studies have demonstrated that complete PV isolation with circular lesions has a better outcome in patients with paroxysmal and persistent AF. In contrast, it may lead to iatrogenic left atrial tachycardia (AT) as an adverse effect of the ablation. Three mechanisms of AT can develop after AF ablation, including macro-reentrant AT, focal AT and PV tachycardia. AT after AF ablation is predominantly related to the arrhythmogenicity of the PVs, lesions created by the ablation procedure and damaged atrial tissue from the persistent tachyarrhythmias. The 3-dimensional maps play an important role in clarifying the mechanism of the tachycardia and the optimal ablation site for ATs.