In all procedures, deep sedation with midazolam, fentanyl, and propofol was used. Left atrial thrombus formation was ruled out prior to the procedure. After application of local anesthesia, the right femoral vein was accessed with three 8 F introducer sheaths. The left atrium (LA) was accessed using a transseptal approach via a steerable sheath (Agilis; Abbott, Abbott Park, North Chicago, Illinois, USA). In case of double transseptal puncture, an 8.5 F SL1 sheath (Abbott, Abbott Park, North Chicago, Illinois, USA) and a modified Brockenbrough technique were used to access the LA. Afterwards, a predefined heparin bolus was applied. Activated clotting time (ACT) was assessed every 15 min throughout the procedures, and heparin was repeatedly administered to maintain an ACT of 300–350 s. A decapolar diagnostic catheter was placed into the coronary sinus.
The DT catheter was used in all procedures and connected to the EnSite X system as demonstrated inFigures 1 and 2 . In all procedures, three-dimensional (3D) electroanatomical mapping was performed using the EnSite X mapping system in NavX mode together with a multipolar mapping catheter (Advisor FL SE or Advisor HD Grid SE; Abbott Laboratories, Abbott Park, North Chicago, Illinois, USA). Procedural data were logged using the electrophysiological (EP) recording system (CardioLab, General Electric, Boston, USA). In all index PVI procedures, a paired, antral, ipsilateral PVI was performed in a point-by-point fashion (Fig. 3 ). Prior to ablation, each pulmonary vein (PV) ostium was carefully registered in the 3D-mapping system after selective angiography. A temperature-controlled mode was used with a maximum tolerated temperature of 60°C. Maximum output power was set to 50 W. In case of repeat procedures, ablation beyond PVI was carried out at the operator’s discretion focusing on substrate modification based on bipolar low-voltage mapping in sinus rhythm (Fig. 4 ).
No esophageal temperature measurement was used because this was not part of our institutional ablation protocol.
The DT catheter was used in all procedures and connected to the EnSite X system as demonstrated in
No esophageal temperature measurement was used because this was not part of our institutional ablation protocol.
