Stockert generator

We used an open irrigated-tip catheter (Celsius, Johnson & Johnson Inc., Diamond Bar, CA, USA; irrigation flow rate 20 to 30 mL/min; 30 W; 47℃) to deliver RF energy for ablation (Stockert generator, Biosense Webster Inc., Diamond Bar, CA, USA). Patients with both PAF and PeAF initially underwent circumferential pulmonary vein isolation (CPVI) and cavotricuspid isthmus block. Following CPVI in PeAF patients, we generated an LA roof line, a posterior inferior line, and an LA anterior line, and confirmed bidirectional blocks by differential pacing.12 (link) Depending on the operator's decision, additional ablations for superior vena cava, non-PV foci or complex fractionated electrogram were conducted. If AF persisted beyond the aforementioned ablation protocols for PAF or PeAF, we stopped the procedure after internal cardioversion. The end point of our procedure was the point of no immediate recurrence of AF after cardioversion with isoproterenol infusion (5 µg/min). If there were non-PV foci under isoproterenol infusion, we ablated them all.

During the procedure, intracardiac electrograms were recorded using a Prucka CardioLab electrophysiology system (General Electric Health Care System Inc). Ablation was guided by 3-dimensional electroanatomical mapping (NavX system; St. Jude Medical Inc). An open irrigation 3.5-mm-tip deflectable catheter (Celsius, Johnson & Johnson Inc; Cool Flex, St. Jude Medical Inc; 30 to 35 W; 47°C) was used for RFCA (Stockert generator; Biosense Webster Inc). All patients initially underwent circumferential pulmonary vein (PV) isolation and cavotricuspid isthmus ablation. For patients with persistent AF, we added a roof line, posterior inferior line, and anterior line19 (link) as a standard lesion set. At the operator’s discretion, additional ablations were delivered to the superior vena cava, non-PV foci, or regions of complex fractionated electrograms. We confirmed the PV isolation by both entrance and exit block and rechecked it under an isoproterenol infusion before finishing the procedure. In addition, we attempted to reinduce AF by isoproterenol infusion with rapid atrial pacing before finishing the procedure. The end point of our procedure was defined as no immediate recurrence of AF after cardioversion while receiving an isoproterenol infusion (5 to 10 μg/min). If there was immediate recurrence of AF after cardioversion, we then ablated these non-PV foci.

Details regarding electrophysiological mapping and RFCA technique and strategy were described in previous studies.17 (link)18 (link) In brief, an open irrigation 3.5-mm-tip deflectable catheter (Celsius, Johnson & Johnson Inc.; Diamond Bar, CA, USA; Coolflex, St. Jude Medical Inc., Minnetonka, MN, USA; 30–35 W; 47℃) was used for RFCA (Stockert generator, Biosense Webster Inc., Diamond Bar, CA, USA). Circumferential pulmonary vein isolation and bi-directional block of the cavotricuspid isthmus ablation were performed in all patients. For patients with persistent AF, we added a roof line, posterior inferior line, and anterior line as a standard lesion set. Additional ablation of the superior vena cava or non-pulmonary vein foci or after complex fractionated electrography was determined by the operator.