Nonfluoroscopic catheter navigation for radiofrequency catheter ablation of supraventricular tachycardia in children

BACKGROUND: Radiofrequency catheter ablation (RCA) of supraventricular tachycardia (SVT) in children is highly successful but requires exposure to radiation. Nonfluoroscopic mapping systems may significantly reduce fluoroscopy time. METHODS: Forty consecutive pediatric patients who underwent RCA for accessory pathways (AP) or AV nodal reentrant tachycardia (AVNRT) with use of a nonfluoroscopic navigation system (Ensite NavX) (group A) were compared retrospectively to 40 consecutive patients with similar diagnoses who underwent RCA with fluoroscopic guidance only (group B). RESULTS: Group A (mean age 12.1+/-2.9 years, mean weight 47+/-13.9 kg) consisted of 11 patients (27.7%) with AVNRT and 29 (72.5%) with AP. Group B (mean age 10.9+/-3.1 years, mean weight 47.1+/-17.1 kg) consisted of 7 patients (17.5%) with AVNRT and 33 (82.5%) with AP. There were no significant differences in AP location, patients with congenital heart disease, and number of radiofrequency lesions. Fluoroscopy time was significantly shorter in group A than in group B (10.4+/-6.1, range 3.1-28.8 minutes, vs 24.9+/-16.0, range 4.4-82.0 minutes, P<0.0001). Procedure duration was also significantly shorter in group A than in group B (170+/-68.5, range 90-420 minutes, vs 218+/-69.3, range 90-360 minutes, P<0.0001). Initial success was 95% in group A and 100% in group B. Tachycardia recurrences occurred in two patients in group A (5%) and six patients in group B (15%). Final success, including repeat ablations for recurrences or failures, was 100% in both groups. CONCLUSIONS: The use of a nonfluoroscopic system for catheter navigation significantly reduced fluoroscopy exposure and total procedure duration of RCA of common SVT substrates in children.