2.4 Ablation procedure
Ablation was guided by the CARTO 3 mapping system, and RF energy was
applied by means of a 3.5-mm open-irrigated-tip catheter (Navistar
ThermoCoolSmartTouch SF; Biosense Webster) at an irrigation flow rate of
17–30 mL/min, power of 25–35 W, and temperature of 45℃, under sedation
achieved by continuous infusion of propofol and dexmedetomidine and
intermittent administration of fentanyl. RF was delivered point-by-point
with a target contact force of >10 g, target ablation
indices of 450 at the anterior wall and 400 at the posterior wall, and
an inter-lesion distance of <6 mm. A real-time automated
tagging module (VisiTag Module, CARTO3; Biosense Webster) was used to
assist in the creation of a contiguous PVI circle. The ipsilateral PVs
were ablated circumferentially, and successful PVI was affirmed by
absence of LA conduction. At least 30 minutes after PVI, 30 mg of
adenosine triphosphate was injected to confirm PV conduction block.
Electrograms were recorded on a LabSystem PRO (Bard Electrophysiology,
Lowell, MA, USA).