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 Discussion This series of cases highlights the feasibility, safety, and efficacy of a zero fluoro approach when treating both AF and different types of atrial arrhythmias, even in the presence of pacemaker leads (and even in pacer-dependent patients). For that matter, it is of utmost importance that ICE, and EA mapping be used to their best advantage. 17-21 Our series represents a pioneer experience in Brazil and Latin America using a radiation-free approach. It resulted from a long-lasting concern about radiation reduction and steady implementation of non-X-ray steps to our ablation protocol. We already had significant expertise from using ICE and EA in every AF case for the last 16 years, which surely made our learning curve easier. In that regard, no increase in costs was seen in our series, as precisely the same catheters were used as in the procedures using fluoroscopy. The ability to use EAM and ICE to provide adequate visualization of every step of the procedure has already been reported. Razminia et al. 22 retrospectively compared safety and efficacy between two groups (60 non-fluoroscopic and 60 fluoroscopic ablation procedures). No significant increase in complications or procedure time was observed, with comparable efficacy. The fluoroscopic group had an average X-ray exposure of 33 minutes in AF ablation cases. Bulava et al. 14 reported on 80 patients randomized to either fluoroscopically-guided PVI or PVI without fluoroscopy using Figure 5 – Distribution of patients according to the type of arrhythmia. AT – atrial tachycardia; CTI – cavotricuspid isthmus. SVT – supraventricular tachycardia (AV node reentry or WPW). CTI, mitral and tricuspid annulus, slow pathway, and crista terminalis. No backup fluoro was used, and no lead apparel was needed in any patient. Interestingly, difficult transseptal puncture (due to small fossa, floppy septum, or fibrous septum), which occurred in 19 patients (20%), was managed without fluoroscopy use in all cases. This is a significant finding, since there is a common belief that transseptal fluoroscopic visualization of the entire sheath-needle assembly is essential both for septal perforation, penetration, and sheath over the wire exchange. All these steps were clearly visualized using ICE to its best advantage. The same applied to the negotiation of tortuous venous branches to advance the ICE catheter – all cases were successfully managed without fluoroscopy by careful visualization of the echo-free space and guidewire insertion. Permanent pacemaker leads were present in 9 patients (9,5%), 7 dual chamber (DDD) pacemakers, and 2CRT-Ddevices with 3 leads (RA, RV, and CS leads). Five patients (56%) were pacemaker-dependent due to complete AV block without any escape rhythm. In 3 of these cases, RA mapping and ablation (CTI and atriotomy scar-related flutters) were performed on top of LA instrumentation and PV isolation. All these cases were also adequately completed without fluoroscopy. Importantly, device interrogations after the procedure did not showany lead damage, dislocation, or threshold changes. Of note, caremust be taken to differentiate the guidewire from lead imaging on ICE. Paroxysmal Afib Persistent Afib Typical Flutter (CTI) SVT AT Paroxysmal Afib 45 47,37% AT 1 1,05% SVT 20 21,05% Typical Flutter (CTI) 5 5,26% Persistent Afib 24 25,26% 1022