Atrial fibrillation cycle length as a predictor for the extent of substrate ablation.
OBJECTIVE
Atrial fibrillation (AF) cycle length (CL) has been demonstrated to be one of the predictors for termination during ablation for AF. We evaluated the AF CL gradient between right atrium (RA) and left atrium (LA) and their mean AF CL in predicting the extent of substrate ablation.


RESULTS
One-hundred and thirty-six patients undergoing first ablation for persistent AF were studied. Stepwise ablation, sequentially in the following order: pulmonary veins (PV), LA, and RA, was performed to achieve AF termination. Stepwise ablation terminated AF in 110 patients (81%). In the AF termination group, AF was terminated by PV isolation (PVI) (Group P), PVI plus LA ablation (Group L), and PVI plus LA plus RA ablation (Group R) in 14 patients (13%), 49 patients (44%), and 47 patients (43%), respectively. Group R had much shorter mean AF CL than Group L (156 ± 18 vs. 174 ± 24 ms, P < 0.001) and mean AF CL in Group L was much shorter than Group P (174 ± 24 vs. 209 ± 36 ms, P = 0.004). The RA to LA AF CL gradient was not significantly different between left-side ablation (Group P + Group L) and additional RA ablation (Group R) (P = 0.177). Mean AF CL >180.50 ms predicted AF termination by PVI (Group P) with 79% sensitivity and 84% specificity while mean AF CL >165.25 ms predicted AF termination by left-side ablation (Group P + Group L) with 67% sensitivity and 75% specificity. After a mean follow-up of 15 ± 7 months, freedom from arrhythmia recurrence was significantly higher in left-side ablation (Group P + Group L) than additional RA ablation (Group R) (P = 0.024).


CONCLUSIONS
Baseline mean AF CL may identify the subset of patients in whom persistent AF can be terminated by different extent of substrate ablation, which may in turn predict the chance of recurrence. However, baseline RA to LA AF CL gradient cannot predict the need for additional RA ablation.
Korea University Anam Hospital, Seoul, Korea johnny_yuen50@hotmail.com.
Ho-Chuen
HC
Yuen
Korea University Anam Hospital, Seoul, Korea.
Seung-Young
SY
Roh
Korea University Anam Hospital, Seoul, Korea.
Dae-In
DI
Lee
Korea University Anam Hospital, Seoul, Korea.
Jinhee
J
Ahn
Korea University Anam Hospital, Seoul, Korea.
Dong-Hyeok
DH
Kim
Korea University Anam Hospital, Seoul, Korea.
Jaemin
J
Shim
Korea University Anam Hospital, Seoul, Korea.
Sang-Weon
SW
Park
Korea University Anam Hospital, Seoul, Korea.
Young-Hoon
YH
Kim
D000368:Aged; D001281:Atrial Fibrillation / Q000601:surgery*; D017115:Catheter Ablation / Q000379:methods*; D004562:Electrocardiography; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006325:Heart Atria / Q000503:physiopathology*; D006801:Humans; D053208:Kaplan-Meier Estimate; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011667:Pulmonary Veins / Q000601:surgery*; D012008:Recurrence; D012680:Sensitivity and Specificity
Atrial fibrillation; Cycle length; Right atrium