Long-term outcomes of remote magnetic navigation for ablation of supraventricular tachycardias

Background: Little is known about the long-term outcomes of catheter ablation of supraventricular tachycardia (SVT) using remote magnetic navigation system (RMN). Methods: One hundred twenty patients underwent catheter ablation of SVTs with RMN (Niobe, Stereotaxis, USA): atrioventricular nodal re-entrant tachycardia (AVNRT; n = 59), atrioventricular re-entrant tachycardia (AVRT; n = 45), and focal atrial tachycardia (AT, n = 16). The outcome of AVRT with right free wall accessory pathway was compared with those of a group of 26 consecutive patients undergoing manual ablation. Results: Mean follow-up period was 2.2 ± 1.4 years. Overall arrhythmia-free survival was 86 %; AVRT (77 %), AVNRT (96 %), and focal AT (71 %). After the learning period (initial 50 cases), procedural outcomes had improved for AVRT and AVNRT (91 % in overall group, 90 % in AVRT group, 100 % in AVNRT group, and 68 % in focal AT group). The recurrence-free rate was higher for the free wall accessory pathways than those of the other sites (92 vs. 73 %, log-rank P = 0.06). Furthermore, when it is confined for the right free wall accessory pathway, RMN showed excellent long-term outcome (7/7, 100 %) compared to the results of manual approach (18/26, 69.2 %, log-rank P = 0.07). Conclusions: RMN showed favorable long-term outcomes for the ablation of SVT. In our experience, RMN-guided ablation may be associated with a higher success rate as compared to manual ablation when treating right-sided free wall pathways.