Is Ablation to Termination the Best Strategy for Ablation of Persistent Atrial Fibrillation?

> “I’ll follow him around the Horn, and around the Norway maelstrom, and around perdition’s flames before I give him up.” > > -Captain Ahab, Moby Dick > “The mysterious thing you look for your whole life will eventually eat you alive.” > > -Laurie Anderson on Moby Dick Optimal strategy and end points for ablation of persistent atrial fibrillation (AF) have not been well established. Although antral pulmonary vein isolation (PVI) is often effective for ablation of paroxysmal AF, it is an insufficient stand-alone strategy for many patients with persistent AF. Selection of adjunctive targets and determination of procedural end points are variable and at the discretion of the operator. Several studies suggested that termination of AF should be the procedural end point during ablation in patients with persistent AF, as a higher probability of maintaining sinus rhythm after the ablation was reported, despite a long procedure duration and a high rate of repeat ablation procedures. However, these studies were not consistently reproducible, and conversion usually occurred to an atrial tachycardia rather than sinus rhythm after extensive ablation. In patients with persistent AF, there is insufficient experimental, mechanistic, or clinical evidence to support termination of AF during ablation as a procedural end point. Response by Lim et al on p 980 Rapid and repetitive depolarizations originating within or at the antra of the pulmonary veins (PVs) and the other thoracic veins are the predominant mechanism in the initiation and perpetuation of paroxysmal atrial fibrillation (PAF).1–3 Antral isolation of PVs and elimination of focal triggers and drivers from other thoracic veins often result in termination and noninducibility of PAF in response to various pharmacological and pacing protocols. Patients with PAF whose AF terminated during ablation and were rendered noninducible, also were more likely to remain in sinus rhythm during long-term clinical follow-up.4 …