Atrial fibrillation: to map or not to map?

Abstract

Isolation of the pulmonary veins may be an effective treatment modality for eliminating atrial fibrillation (AF) episodes but unfortunately not for all patients. When ablative therapy fails, it is assumed that AF has progressed from a trigger-driven to a substrate-mediated arrhythmia. The effect of radiofrequency ablation on persistent AF can be attributed to various mechanisms, including elimination of the trigger, modification of the arrhythmogenic substrate, interruption of crucial pathways of conduction, atrial debulking, or atrial denervation. This review discusses the possible effects of pulmonary vein isolation on the fibrillatory process and the necessity of cardiac mapping in order to comprehend the mechanisms of AF in the individual patient and to select the optimal treatment modality.

2012 HRS/EHRA/ECAS Expert Consensus Statement on Catheter and Surgical Ablation of Atrial Fibrillation: Recommendations for Patient Selection, Procedural Techniques, Patient Management and Follow-up, Definitions, Endpoints, and Research Trial Design

“…Over time, AF progresses from a trigger-driven to a more substrate-mediated arrhythmia due to structural remodeling of the atria. 153,243 Ablative therapy is therefore aimed at either eliminating the trigger initiating AF or modifying the arrhythmogenic substrate. The most commonly employed ablation strategy consists of electrical isolation of the PVs by creation of circumferential lesions around the right and the left PV.…”

Relevance of Conduction Disorders in Bachmann’s Bundle During Sinus Rhythm in Humans

“…[16][17][18][19] Color-coded activation maps of every SR beat were automatically created by marking the steepest negative deflection of extracellular potentials. An averaged SR activation map was then constructed by time alignment of all individual beats recorded during 5 seconds of SR, thereby excluding aberrant and atrial premature beats.…”

Wave-Mapping as a Guide for Ablation of Atrial Fibrillation

“…[4][5][6][7][8] In a recent study from Australia, in only 3 of 18 patients, a transient rotational circuit was observed that survived not longer than just a few cycles. 6 In a large still ongoing study in patients with induced and persistent AF, in whom all accessible epicardial areas are mapped (>1500 points/patient), 7 to date not a single rotor could be found. So, if in diseased human atria reentrant circuits have such a short life-time, what then is the source of the numerous fibrillation waves that occupy the atria uninterruptedly for so many years?…”

“…[4][5][6][7][8][9][10][11] Although low-resolution mapping studies with multipolar basket catheters claim that the majority of clinical AF is attributable to the presence of a single large mother rotor, 12,13 high resolution mapping performed during cardiac surgery has been unable to detect reentrant circuits. [4][5][6][7][8] In a recent study from Australia, in only 3 of 18 patients, a transient rotational circuit was observed that survived not longer than just a few cycles. 6 In a large still ongoing study in patients with induced and persistent AF, in whom all accessible epicardial areas are mapped (>1500 points/patient), 7 to date not a single rotor could be found.…”