The Electrical Characteristics and Clinical Significance of the Effect of Adenosine on Dissociated Activity after Circumferential Venous Isolation in Patients with Atrial Fibrillation.
BACKGROUND
Dissociated activity can occur after circumferential thoracic vein isolation for treating atrial fibrillation (AF). However, its clinical significance and response to adenosine remain unclear.


METHODS
Fifty-three patients (10 women, 11 with non-paroxysmal AF, with mean age 54.4 ± 11.2 years) with slow dissociated activity after thoracic vein isolation for AF ablation were analyzed. Adenosine (12 mg) was injected intravenously into 30 patients, and the responses of the dissociated activities were recorded.


RESULTS
The clinical characteristics and the rate of recurrence did not differ between patients with and without dissociated activity. Dissociated activity was most frequently observed at the right superior pulmonary vein (PV) (61%), left superior PV (26%), right inferior PV (5%), left inferior PV (4%), and non-PV sites (4%). The locations of dissociated activities were associated with the AF trigger sites (p = 0.004). Adenosine injection decreased the cycle length of dissociated activity in 13 patients (group 1) and increased it in 17 patients (group 2). Dissociated activity disappeared in 7 patients (41%) (group 2) after adenosine injection. During the mean 33 ± 17 months of follow-up, group 2 patients had a lower AF recurrence rate (24%) than group 1 patients (62%) (p = 0.035).


CONCLUSIONS
The locations of dissociated activity were closely associated with the AF trigger sites. The responses to adenosine may predict AF recurrence in patients with dissociated activity.


BACKGROUND
Ablation; Atrial fibrillation; Dissociated activity.
Division of Cardiology, Department of Internal Medicine, Chang Bing Show Chwan Memorial Hospital, Changhua;
Ya-Lei
YL
Niu
Department of Medicine and Institute of Clinical Medicine, Cardiovascular Research Center, National Yang-Ming University School of Medicine; ; Division of Cardiology, Department of Internal Medicine, Taipei Veterans General Hospital, Taipei;
Shih-Lin
SL
Chang
Department of Medicine and Institute of Clinical Medicine, Cardiovascular Research Center, National Yang-Ming University School of Medicine; ; Division of Cardiology, Department of Internal Medicine, Taipei Veterans General Hospital, Taipei;
Yenn-Jiang
YJ
Lin
Department of Medicine and Institute of Clinical Medicine, Cardiovascular Research Center, National Yang-Ming University School of Medicine; ; Division of Cardiology, Department of Internal Medicine, Taipei Veterans General Hospital, Taipei;
Li-Wei
LW
Lo
Department of Medicine and Institute of Clinical Medicine, Cardiovascular Research Center, National Yang-Ming University School of Medicine;
Yu-Feng
YF
Hu
Department of Medicine and Institute of Clinical Medicine, Cardiovascular Research Center, National Yang-Ming University School of Medicine;
Ta-Chuan
TC
Tuan
Department of Cardiology, Chung Shan Medical University Hospital, Taichung;
Chin-Feng
CF
Tsai
Division of Cardiology, Department of Internal Medicine, Tri-Service General Hospital;
Wei-Shiang
WS
Lin
Department of Medicine and Institute of Clinical Medicine, Cardiovascular Research Center, National Yang-Ming University School of Medicine; ; Division of Cardiology, Department of Internal Medicine, Taipei Veterans General Hospital, Taipei; ; Division of Cardiology, Department of Internal Medicine, National Yang-Ming University Hospital, Taipei, Taiwan.
Hsuan-Ming
HM
Tsao
Department of Medicine and Institute of Clinical Medicine, Cardiovascular Research Center, National Yang-Ming University School of Medicine; ; Division of Cardiology, Department of Internal Medicine, Taipei Veterans General Hospital, Taipei;
Shih-Ann
SA
Chen