Organized Atrial Tachycardias after Atrial Fibrillation Ablation

Abstract

The efficacy of catheter-based ablation techniques to treat atrial fibrillation is limited not only by recurrences of this arrhythmia but also, and not less importantly, by new-onset organized atrial tachycardias. The incidence of such tachycardias depends on the type and duration of the baseline atrial fibrillation and specially on the ablation technique which was used during the index procedure. It has been repeatedly reported that the more extensive the left atrial surface ablated, the higher the incidence of organized atrial tachycardias. The exact origin of the pathologic substrate of these trachycardias is not fully understood and may result from the interaction between preexistent regions with abnormal electrical properties and the new ones resultant from radiofrequency delivery. From a clinical point of view these atrial tachycardias tend to remit after a variable time but in some cases are responsible for significant symptoms. A precise knowledge of the most frequent types of these arrhythmias, of their mechanisms and components is necessary for a thorough electrophysiologic characterization if a new ablation procedure is required.

Catheter Ablation of Lone Atrial Fibrillation

“…However, circumferential antral PV isolation, particularly if it is combined with additional modification of AF substrate, whether by the linear LA ablation and/or CFAE ablation, may lead to the occurrence of atrial tachycardia in 7.6%-44% of patients [24,42,54,[194][195][196]. After usage of similar ablative strategy (CFAE + PVI), post-procedural incidence of atrial tachycardia was remarkably higher after the ablation of persistent AF than after the ablation of paroxysmal AF (20.0% vs. 2.4%) [197].…”

“…The diagnosis is definitely made by an electrophysiological study, through conventional activation mapping and entrainment mapping [196]. The use of 3D-mapping systems may facilitate atrial tachycardia mapping and ablation [195].…”

“…However, in most of those patients (79%) a new type of atrial tachycardia was registered [194,196,200,201]. A 47-year-old male underwent catheter ablation due to a 10-year history of daily attacks of symptomatic paroxysmal lone AF, refractory to drug therapy with beta-blockers, sotalol, propafenone, and, finally flecainide.…”

Approach to catheter ablation of left atrial flutters

“…Macroreentry is the mechanism of most ATs after pulmonary vein isolation (about 60%‐70%), whereas the remainder are classified as focal mechanisms . When more extensive substrate ablation is performed for AF, ATs are more likely to occur.…”

“…9 Macroreentry is the mechanism of most ATs after pulmonary vein isolation (about 60%-70%), whereas the remainder are classified as focal mechanisms. 10,11 When more extensive substrate ablation is performed for AF, ATs are more likely to occur. For example, after a stepwise approach to ablation of persistent AF, organized ATs can occur in up to 40% of patients during follow up.…”