Predictors of ectopic firing from the superior vena cava in patients with paroxysmal atrial fibrillation.
OBJECTIVE
Although catheter ablation targeting the pulmonary vein (PV) is a well-known therapy for patients with paroxysmal atrial fibrillation (PAF), ectopic firings from the superior vena cava (SVC) can initiate PAF. The purpose of this study was to investigate predictors of SVC firing.


METHODS
The subjects included 336 consecutive PAF patients (278 males, age 56.1 ± 10.8 years) undergoing atrial fibrillation (AF) ablation. The appearance of SVC firing was monitored throughout the procedure using a decapolar catheter with multiple electrodes to record electrograms of the coronary sinus and SVC. In addition to PV isolation, SVC isolation was performed only in patients with documented SVC firing.


RESULTS
SVC firing was observed in 43/336 (12.8 %) of the patients, among whom complete isolation of the SVC was achieved in 40/43 (93 %) patients. A lower body mass index (BMI) (22.8 ± 2.8 vs 24.1 ± 3.1 kg/m(2), p = 0.007) and higher prevalence of prior ablation procedures (58 vs 18 %, p = 0.0001) were related to the presence of SVC firing. In a multivariate analysis, a lower BMI (p = 0.012; odds ratio 0.83, 95 % CI 0.72 to 0.96) and history of prior ablation procedures (p < 0.0001; odds ratio 5.37, 95 % CI 2.71 to 10.63) were found to be independent predictors of the occurrence of SVC firing. Among 96 patients undergoing repeat ablation procedures, less PV-left atrial re-conduction was observed in patients with SVC firing than in those without (2.7 ± 1.2 vs 3.2 ± 0.8, p = 0.02).


CONCLUSIONS
The presence of SVC firing in patients with PAF is associated with a history of repeat ablation procedures and lower BMI values.
Department of Cardiology, The Jikei University School of Medicine, 3-25-8, Nishi-Shinbashi, Minato-ku, Tokyo, 105-8471, Japan, inadi@jikei.ac.jp.
Keiichi
K
Inada
Seiichiro
S
Matsuo
Ken-ichi
K
Tokutake
Ken-ichi
K
Yokoyama
Mika
M
Hioki
Ryohsuke
R
Narui
Keiichi
K
Ito
Shin-ichi
S
Tanigawa
Seigo
S
Yamashita
Michifumi
M
Tokuda
Kenri
K
Shibayama
Satoru
S
Miyanaga
Ken-ichi
K
Sugimoto
Michihiro
M
Yoshimura
Teiichi
T
Yamane
D001281:Atrial Fibrillation / Q000175:diagnosis / Q000453:epidemiology* / Q000601:surgery*; D018880:Atrial Premature Complexes / Q000175:diagnosis / Q000453:epidemiology* / Q000517:prevention & control*; D018780:Body Surface Potential Mapping / Q000706:statistics & numerical data; D017115:Catheter Ablation / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012008:Recurrence; D018570:Risk Assessment; D012307:Risk Factors; D016896:Treatment Outcome; D014683:Vena Cava, Superior / Q000601:surgery*