ABC | Volume 114, Nº6, June 2020

Original Article Saad et al. Zero Fluoroscopy Catheter Ablation for Atrial Fibrillation and Supraventricular Arrhythmias Arq Bras Cardiol. 2020; 114(6):1015-1026 appendage was visualized on ICE (with the catheter placed in the right ventricle or in the LA cavity itself – figure 2) and its position manually annotated in the EA map. After calibrating the contact sensor, point-by-point circumferential PV isolation was performed for both pairs of veins (figure 3 and video 4), using 40W of maximal power and contact force between 10- 20g. Whenever esophageal temperature rose in the posterior segments, shorter (5-10 seconds) RF applications and/or lower power (25-30W) were used. Adenosine challenge (18 mg) was used to confirmed PV isolation without dormant conduction. High-dose Isoproterenol infusion at a rate of 20 mcg/10 min was performed in search of inducible extra-pulmonary foci, Figure 1 – ICE imaging sequence showing the steps for the zero-fluoro double transseptal puncture.A)Aguidewire (arrow) is advanced to the superior vena cava (SVC); in the picture, the right atrium (RA) is also visualized, as well as the right atrial appendage (*), confirming correct wire positioning. B) A long transseptal sheath (arrow) is advanced over the wire to the SVC, erasing the brightness of the wire as it is advanced. C) The transseptal sheath + needle assembly (arrow) in the SVC, to be pulled down to the fossa ovalis. The left atrium (LA) is visualized, as well as a transseptal access that has been previously performed. D) Sheath + needle (arrow) pulldown along the septum on its way to the fossa ovalis. E) Sheath + needle tenting the fossa ovalis (arrow), confirming adequate positioning to provide access to the LA. F) Puncture of the fossa ovalis (FO) and needle enhancement visualized in the LA cavity (arrow). The transseptal puncture is performed in a posterior location, confirmed by visualization of the left inferior PV (LIPV) in the ultrasound plane. Video 1 – Catheter insertion from the femoral access to the RA guided by the electroanatomic mapping system. After the catheters arrive in the RA (decapolar catheter followed by the ablation catheter [RF]), marked by the appearance of electrograms, the RA anatomy is created, followed by cannulation of the coronary sinus (CS) – first by the RF catheter and followed by the decapolar one. Access the video here: https://bit.ly/2XWhIbE. 1017