Feasibility study of endocardial mapping of ganglionated plexuses during catheter ablation of atrial fibrillation.
BACKGROUND
Numerous reports have demonstrated an association between autonomic tone and atrial fibrillation (AF). Pulmonary vein (PV) denervation during catheter ablation of AF has been shown to significantly reduce recurrence of AF.


OBJECTIVE
The purpose of this study was to assess the safety and efficacy of high-frequency stimulation at mapping cardiac ganglionated plexuses in patients undergoing catheter ablation of AF.


METHODS
Fourteen patients with a history of symptomatic AF underwent a single transseptal approach and electroanatomic mapping of the left atrium, right atrium, and coronary sinus. Using high-frequency stimulation with patients under general anesthesia (20-50 Hz, 5-15 V, pulse width 10 ms), mapping of ganglionated plexuses was performed. Radiofrequency (RF) ablation was performed during AF guided by complex fractionated atrial electrograms. Lesions were mostly delivered circumferentially in the antral area of the PVs, predominantly over and adjacent to regions of ganglionated plexuses.


RESULTS
There was a mean of 4 +/- 1 (range 2-6) ganglionated plexuses per patient, and a mean total of 3 +/- 1 RF applications were delivered over positive vagal sites. Although a vagal response occurred infrequently during ablation (0.9%), postablation high-frequency stimulation failed to provoke a vagal response in 30 (88%) of 34 previously positive vagal sites that underwent ablation.


CONCLUSIONS
Ganglionated plexuses can be precisely mapped using high-frequency stimulation and are located predominantly in the path of lesions delivered during ablation of AF. Objective documentation of modification of autonomic tone can be documented in the majority of patients. Future studies are required to determine the specific role of mapping and targeting of ganglionated plexuses in patients undergoing catheter ablation of AF.
Lemery
Robert
R
Division of Cardiology, University of Ottawa Heart Institute, Ontario, Canada. RLemery@ottawaheart.ca
Birnie
David
D
Tang
Anthony S L
AS
Green
Martin
M
Gollob
Michael
M
D000328:Adult; D000344:Afferent Pathways / Q000503:physiopathology; D000368:Aged; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000188:drug therapy / Q000503:physiopathology* / Q000601:surgery*; D016275:Atrial Function; D001341:Autonomic Nervous System / Q000503:physiopathology; D018780:Body Surface Potential Mapping; D017115:Catheter Ablation / Q000009:adverse effects; D004525:Efferent Pathways / Q000503:physiopathology; D004558:Electric Stimulation; D022062:Electrophysiologic Techniques, Cardiac; D004699:Endocardium / Q000294:innervation / Q000503:physiopathology*; D005240:Feasibility Studies; D005500:Follow-Up Studies; D006329:Heart Conduction System / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D012107:Research Design; D016896:Treatment Outcome
D000889:Anti-Arrhythmia Agents