"Near-zero" fluoroscopic exposure in supraventricular arrhythmia ablation using the EnSite NavX™ mapping system: personal experience and review of the literature.

PURPOSE: Radiofrequency catheter ablation (RFCA) of supraventricular tachyarrhythmias carries a small but non-negligible radiation risk. Studies in children already showed the feasibility of using three-dimensional mapping systems as the primary guide for catheter visualization and positioning in these RFCAs. We aim to demonstrate the feasibility and safety of such an approach in young and middle-aged patients.

METHODS: Fifty patients (age 34 ± 12) with supraventricular tachyarrhythmias underwent electrophysiological study; of these, 47 patients proceeded to RFCA guided by the EnSite NavX(TM) system (23 with atrioventricular nodal reentry tachycardia, 16 with an accessory pathway, six with typical atrial flutter, and two with right atrial tachycardia).

RESULTS: In 38/50 cases (76%), electroanatomical mapping avoided fluoroscopy entirely, including four cases requiring access to the left heart chambers by a retrograde approach. In the remaining 12/50 cases (24%), fluoroscopy use was limited to 122 ± 80 s, with a correspondingly low radiation exposure (dose area product 1.3 ± 1.1 mGy × m(2)). All procedures were acutely successful, with a procedural time of 113 ± 37 minutes, and without incurring in any major complication. Over a mean follow-up of 12 ± 3 months, we observed one recurrence of pre-excitation and one relapse of atrial flutter.

CONCLUSIONS: Our study shows that non-fluoroscopic RFCA of supraventricular tachyarrhythmias using the EnSite NavX(TM) system is feasible, safe, and effective in a population of relatively young adults. Our experience of a non-fluoroscopic approach in these procedures deserves consideration, particularly in the young or in other patients at higher radiation risk.