Background: No data exist on the ability of the novel Rhythmia 3-D mapping system to minimize fluoroscopy exposure during transcatheter ablation of arrhythmias. We report data on the feasibility and safety of a minimal fluoroscopic approach using this system in supraventricular tachycardia (SVT) procedures.Methods: Consecutive patients were enrolled in the CHARISMA registry at 12 centers. All right-sided procedures performed with the Rhythmia mapping system were analyzed. The acquired electroanatomic information was used to reconstruct 3-D cardiac geometry; fluoroscopic confirmation was used whenever deemed necessary.Results: Three hundred twenty-five patients (mean age = 56 ± 17 years, 57% male) were included: 152 atrioventricular nodal reentrant tachycardia, 116 atrial flutter, 41 and 16 right-sided accessory pathway and atrial tachycardia, respectively.Overall, 27 481 s of fluoroscopy were used (84.6 ± 224 s per procedure, equivalent effective dose = 1.1 ± 3.7 mSv per patient). One hundred ninety-two procedures (59.1%) were completed without the use of fluoroscopy (zero fluoroscopy, ZF). In multivariate analysis, the presence of a fellow in training (OR = 0.15, 95% CI: 0.05-0.46; p = .0008), radiofrequency application (0.99, 0.99-1.00; p = .0002), and mapping times (0.99, 0.99-1.00; p = .042) were all inversely associated with ZF approach. Acute procedural success was achieved in 97.8% of the cases (98.4 vs.