The different mechanisms between late and very late recurrences of atrial fibrillation in patients undergoing a repeated catheter ablation.
BACKGROUND
The mechanisms of late (<1 year after the ablation) and very late (>1 year after the ablation) recurrences of paroxysmal atrial fibrillation (AF) after catheter ablation have not been reported.


RESULTS
Fifty consecutive patients undergoing a repeated electrophysiologic study to investigate the recurrence of paroxysmal AF after the first ablation were included. Group 1 consisted of 12 patients with very late (26 +/- 13 months) and group 2 consisted of 38 patients with late (3 +/- 3 months) recurrence of paroxysmal AF. In the baseline study, group 1 had a lower incidence of AF foci from the pulmonary veins (PVs) (67% vs 92%, P = 0.048) and a higher incidence of AF foci from the right atrium (50% vs 13%, P = 0.014) than group 2. In the repeated study, group 1 had a higher incidence of AF foci from the right atrium (67% vs 3%, P < 0.001) and a lower incidence of AF foci from the left atrium (50% vs 97%, P < 0.001), including a lower incidence of AF foci from the PVs (50% vs 79%, P = 0.07) and from the left atrial free wall (0% vs 29%, P = 0.046) than group 2. Furthermore, most of these AF foci (64% of group 1, 65% of group 2) were from the previously targeted foci.


CONCLUSIONS
The right atrial foci played an important role in the very late recurrence of AF, whereas the left atrial foci (the majority were PVs) were the major origin of the late recurrence of AF after the catheter ablation of paroxysmal AF.
Hsieh
Ming-Hsiung
MH
Division of Cardiovascular Medicine, Department of Medicine, Taipei Medical University School of Medicine, and Taipei Wan-Fang Hospital, Taipei, Taiwan.
Tai
Ching-Tai
CT
Lee
Shih-Huang
SH
Lin
Yung-Kuo
YK
Tsao
Hsuan-Ming
HM
Chang
Shih-Lin
SL
Lin
Yenn-Jiang
YJ
Wongchaoen
Wanwarang
W
Lee
Kun-Tai
KT
Chen
Shih-Ann
SA
D001281:Atrial Fibrillation / Q000453:epidemiology / Q000503:physiopathology / Q000601:surgery*; D017115:Catheter Ablation; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D012008:Recurrence; D012086:Reoperation; D016896:Treatment Outcome