Characterization of electrograms associated with termination of chronic atrial fibrillation by catheter ablation.
OBJECTIVE
This study sought to determine the characteristics of atrial electrograms predictive of slowing or termination of atrial fibrillation (AF) during ablation of chronic AF.


BACKGROUND
There is growing recognition of a role for electrogram-based ablation.


METHODS
Forty consecutive patients (34 male, 59 +/- 10 years) undergoing ablation for chronic AF persisting for a median of 12 months (range 1 to 84 months) were included. After pulmonary vein isolation and roof line ablation, electrogram-based ablation was performed in the left atrium and coronary sinus. Targeted electrograms were acquired in a 4-s window and characterized by: 1) percentage of continuous electrical activity; 2) bipolar voltage; 3) dominant frequency; 4) fractionation index; 5) mean absolute value of derivatives of electrograms; 6) local cycle length; and 7) presence of a temporal gradient of activation. Electrogram characteristics at favorable ablation regions, defined as those associated with slowing (a >or=6-ms increase in AF cycle length) or termination of AF were compared with those at unfavorable regions.


RESULTS
The AF was terminated by electrogram-based ablation in 29 patients (73%) after targeting a total of 171 regions. Ablation at 37 (22%) of these regions was followed by AF slowing, and at 29 (17%) by AF termination. The percentage of continuous electrical activity and the presence of a temporal gradient of activation were independent predictors of favorable ablation regions (p = 0.016 and p = 0.038, respectively). Other electrogram characteristics at favorable ablation regions were not significantly different from those at unfavorable ablation regions.


CONCLUSIONS
Catheter ablation at sites displaying a greater percentage of continuous activity or a temporal activation gradient is associated with slowing or termination of chronic AF.
Takahashi
Yoshihide
Y
Service de Rythmologie, Hôpital Cardiologique du Haut-Lévêque, Université Victor Segalen Bordeaux 2, Bordeaux, France. yoshihide_takahashi@oboe.ocn.ne.jp
O'Neill
Mark D
MD
Hocini
Mélèze
M
Dubois
Rémi
R
Matsuo
Seiichiro
S
Knecht
Sébastien
S
Mahapatra
Srijoy
S
Lim
Kang-Teng
KT
Jaïs
Pierre
P
Jonsson
Anders
A
Sacher
Frédéric
F
Sanders
Prashanthan
P
Rostock
Thomas
T
Bordachar
Pierre
P
Clémenty
Jacques
J
Klein
George J
GJ
Haïssaguerre
Michel
M
D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000188:drug therapy / Q000503:physiopathology* / Q000601:surgery; D017115:Catheter Ablation; D004562:Electrocardiography; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006331:Heart Diseases / Q000150:complications; D006801:Humans; D008297:Male; D008875:Middle Aged
D000889:Anti-Arrhythmia Agents