Navistar rmt ther mocool

Antiarrhythmic drug therapy was not interrupted for patients prior to CA procedures. A decapolar catheter was advanced into the coronary sinus (CS), and AF was induced with decremental atrial burst pacing in all cases if the patient arrived in the electrophysiology lab in sinus rhythm. To reach activated clotting time (ACT) > 300 s before the introduction of the basket catheter, intravenous heparin was administered for every patient. Sustained AF of more than 5-min duration was recorded using a 64-pole basket catheter (FIRMap, Abbott, Abbott Park, IL, USA), which was introduced through an 8.5 Fr SL1 sheath in the RA and later in the LA. In redo cases, isolation of the PVs was checked and re-PVI was completed whenever necessary. The basket catheter was introduced into the LA and EGF mapping was performed. Using the EGF mapping software (Ablamap^®, Ablacon, Inc., Wheat Ridge, CO, USA), clinically relevant active AF sources above the threshold (see below) were identified and then ablated using a 3.5 mm irrigated-tip catheter (Navistar^® RMT ThermoCool^®, Biosense Webster, Irvine, CA, USA). Radiofrequency energy was applied with the following power settings: 25–50 W, temperature limit 43°C, flow rate 17–30 ml/min, using the Stereotaxis remote magnetic navigation system (Stereotaxis, St. Louis, MO, USA). In some cases, an extensive ablation at the LAA level was necessary.

As described previously [10 (link)], the open-irrigated ablation catheter (NaviStar™ RMT ThermoCool™; Biosense Webster, CA, USA) was connected to a 3D mapping system (CARTO™, Biosense Webster, CA, USA or EnSite™, St. Jude Medical, MN, USA) and the RMN Niobe™ ES system (Stereotaxis Inc., St. Louis, MO, USA) to perform 3D LA electroanatomic mapping and ablation. Additional fracture potential ablation or linear ablation might be performed when necessary. The RF current was delivered for 30−40 s per lesion, applying 30–40 W (irrigation flow rate 17 mL/min) with the generator (Stockert, Biosense Webster, CA, USA) in a power-controlled mode. Power was selected based on the location of catheter tip in the LA. Once PV isolation was achieved, electrical cardioversion was attempted. For patients whose rhythm could not be converted to the sinus rhythm, the LA roof line lesion was created by the RMN catheter or cryoballoon, respectively in either group to ease subsequent electrical cardioversion. Substrate modification, such as ablation of complex fractionated atrial electrogram, was not allowed in this study.