Efficacy and safety of zero-fluoroscopy ablation of ventricular arrhythmias originating from the right ventricular outflow tract: Comparison with fluoroscopy-guided ablation without a three-dimensional electroanatomic mapping system

Background: Radiofrequency catheter ablation is the preferred treatment choice for ventricular arrhythmias (VAs) originating from right ventricular outflow tract (RVOT) in symptomatic patients and is usually performed under fluoroscopy guidance. Zero-fluoroscopy (ZF) ablations using 3D mapping system applied for treatment of various types of arrhythmias are trending and practiced in many centers around the world, but rarely done in Vietnam. The objective of this study was to evaluate the efficacy and safety of zero-fluoroscopy ablation of RVOT VAs, compared with fluoroscopy-guided ablation without a 3D electroanatomic mapping (EAM) system.

Methods and results: We conducted a nonrandomized, prospective single-center study including 114 patients with RVOT VAs that had electrocardiographic features of typical left bundle branch block, inferior axis QRS morphology, and a precordial transition ≥ V₃, from May 2020 to July 2022. The patients were assigned (without randomization) to two different approaches of either zero-fluoroscopy ablation under the guidance of the Ensite system (ZF group) or fluoroscopy-guided ablation without a 3D EAM (fluoroscopy group) in a 1:1 ratio. After a follow-up time of 5.0 ± 4.9 months and 6.9 ± 9.3 months in the ZF and fluoroscopy groups, respectively, the results showed a higher success rate in the fluoroscopy group than in the complete ZF group (87.3% vs 86.8%), although the difference was not statistically significant. No major complication was noted in both the groups.

Conclusion: ZF ablation for RVOT VAs can be done safely and effectively using the 3D electroanatomic mapping system. The results of ZF approach are comparable to that of the fluoroscopy-guided approach without a 3D EAM system.