Efficacy of Electroanatomical Mapping for Radiofrequency Ablation of Right‐sided Accessory Pathways

Introduction: Due to the difficulty in performing detailed mapping around the tricuspid annulus and the high occurrence of mechanical trauma during the procedure, the outcome of right‐sided accessory pathway (AP) ablation still has a relatively high primary failure and recurrence rate. Methods and Results: Six patients with right free‐wall APs underwent electroanatomical mapping. The AP had retrograde unidirectional conduction in 3 patients, anterograde unidirectional conduction in 1 patient, and bidirectional conduction in 2 patients. The right atrial (RA) activation map was constructed during right ventricular (RV) pacing (n = 5), and the RV activation map was constructed during RA pacing (n = 3). During mapping, the AP conduction was interrupted by catheter mechanical trauma in 3 patients. The first RF application successfully eliminated the AP conduction within 2 seconds in 3 patients with concealed pathways. In the remaining 3 patients, rescue RF energy was delivered at the tagged bump site on the map. The mean procedure time was 214 ± 77 minutes, and mean fluoroscopy time 63 ± 23 minutes. No recurrence occurred during 12 ± 3.2 months of followup in any of the patients. Conclusions: With the guidance of an electroanatomical mapping system, right‐sided accessory pathways can be satisfactorily eliminated without later recurrence.