Ablation Procedure
We performed all RFCA procedures under deep sedation. A duo-decapolar
electrode catheter (BeeAT, Japan Lifeline, Tokyo, Japan) was inserted
into the coronary sinus (CS) from the right internal jugular vein. Two
long sheaths (Swarts and Agilis, Abbott, St. Paul, MN) were advanced
into the left atrium through a single transseptal puncture via the right
femoral vein. A duo-decapolar ring catheter (Lasso, Biosense Webster,
Irvine, CA) was used to record pulmonary vein (PV) potential. Patients
were anticoagulated with intravenous heparin to maintain an activated
clotting time > 300 seconds. All patients underwent
circumferential PVI by isolating the left and right PVs as ipsilateral
common ostia on the 3D-geometry of the left atrium (Carto 3, Biosense
Webster). In patients with a long superior vena cava (SVC) sleeve
(> 30 mm) or in whom ectopic beats originating from the SVC
triggered AF, electrical isolation of the SVC was performed as
previously described.5Isolation of the posterior wall of the left atrium (PLA) was performed
depending on the operators’
discretion.6
In the Non-CF group, ablation was performed with a 3.5-mm tip, 56-hole
irrigated catheter (THERMOCOOL SF; Biosense Webster). In the CF group, a
3.5-mm tip, 56-hole irrigated catheter with a CF sensor (THERMOCOOL
SMARTTOUCH SF, Biosense Webster) was used for ablation. Power settings
were 25–30 W for the posterior wall and 30–35 W for other regions of
the left atrium. In the Non-CF group, the RF current was delivered for
20–40 seconds to each lesion, until local bipolar electrograms
decreased. If intra-esophageal temperature rose > 39.5℃
during ablation, RF delivery was interrupted.