Visitag

After 2 separate transseptal punctures, a Mullins transseptal and a 9 F steerable Agilis sheath were placed in the LA. A circular decapolar Lasso catheter and a contact force ablation catheter were advanced through the Mullins and the Agilis sheath, respectively. A 3D anatomical map of the LA was obtained using the Carto Merge System®. Predefined lines for the ablation circles were tagged in the antrum of the PVs. Point-by-point IRF ablation was performed isolating the left and the right PVs in separate circles. RF energy was delivered in power-controlled mode without ramping using 30–35W on anterior segments and 20–25W on posterior wall with an irrigation flow of 17 cc/min. Energy was delivered for 30 s at each site after obtaining a target contact force >6 g. Ablation tags were displayed using Visitag® (Biosense-Webster Inc, Diamond Bar, CA, USA). PVI in each PV was assessed based on signals recorded through electrodes of the Lasso catheter.

After puncturing jugular and femoral veins, under the guidance of X-ray or intracardiac echocardiography, a decapolar catheter was inserted into the coronary sinus, and a single transseptal puncture was made with a Swartz sheath (Abbott, Chicago, USA). After the transseptal puncture, Heparin was given at a dose of 100 U/kg body weight, and it was given again to keep the activated clotting time between 300 and 350 s. Under the direction of an electro-anatomy mapping system (EAM; Biosense Webster, Irvine, USA), mapping and ablation were performed by experienced electrophysiological doctors, using a Pentaray mapping catheter (Biosense Webster, Irvine, USA) and Thermocool Smart touch SF catheter (Biosense Webster, Irvine, USA). Ablation points were marked automatically according to VisiTag (Biosense Webster, Irvine, USA) settings. (The size of the lesion tag was set at 2.5 mm, minimum time 3 s.) Throughout the process, the irrigation flow was 15 ml per minute and the radiofrequency (RF) power was set to 45 W.

An open-irrigated, 3.5-mm tip, contact-force sensing radiofrequency (RF) ablation catheter (ThermoCool SmartTouch, Biosense Webster Inc.) was used, and with a power-controlled mode, ablation lesions were created by delivering 20–35 W (depending on anterior or posterior location) for 20–40 s per lesion during irrigation at a rate of 17–30 ml/min. We do not use esophageal temperature probe. A wide area of PV antral isolation was targeted. All lesion markers within the EAM were created using automated lesion annotation (VisiTag, Biosense Webster, Inc.). Ablation was continued until complete circumferential antral isolation and closure of all possible gaps in the ablation line. Entrance and exit block were both confirmed in every isolated vein. Heparin was given throughout the procedure to maintain an activated clotting time (ACT) of around 300 s. With patient with documented atrial flutter, Cavo-tricuspid isthmus isolation was done at the end of the procedure with achieving complete bidirectional block.