Zero-Fluoroscopy Ablation of Accessory Pathways in Children and Adolescents: CARTO3 Electroanatomic Mapping Combined with RF and Cryoenergy.

BACKGROUND: Fluoroscopic catheter ablation of cardiac arrhythmias in pediatric patients exposes the patients to the potential risk of radiation considering the sensitivity of this population and its longer life expectancy. We evaluated the feasibility, safety, and efficacy of accessory pathway (AP) ablation guided by CARTO3 electroanatomic mapping (EAM) system with both cryoenergy and radiofrequency (RF) energy in order to avoid x-ray exposure in pediatric patients. METHODS: We included 44 patients (mean age: 13.1 ± 3.3 years); nine of 44 presented concealed AP. An electrophysiological study with a three-dimensional EAM reconstruction was performed in every patient with a venous transfemoral direct right atrium approach or an arterial transfemoral retrograde approach to reach the mitral annulus. In two patients with left-sided AP, the ablation was performed via a patent foramen ovale. RESULTS: A total of 47 APs were present, left sided in 45% (21/47) of cases (15 lateral, one anterior, three posteroseptal, and two posterolateral) and right sided in 55% (26/47; one anterior, three anterolateral, one posterolateral, three lateral, five para-Hisian, 12 posteroseptal, and one anteroseptal). Ablation without the use of fluoroscopy was successfully performed in every patient (33 with RF and in 11 with cryoenergy). No complication occurred. At a mean follow-up of 16.0 ± 11.7 months, we observed seven recurrences, three of them successfully re-ablated without fluoroscopy. In one case cryoablation of a para-Hisian AP was ineffective in the long term. CONCLUSIONS: Three-dimensional EAM allowed a safe and effective fluoroless AP ablation procedure in a pediatric population both with RF and cryoenergy.

Single center experience of fluoroless AVNRT ablation guided by electroanatomic reconstruction in children and adolescents.

BACKGROUND: Anatomical considerations and risks related to x-ray exposure make atrioventricular nodal reentrant tachycardia (AVNRT) ablation in pediatric patients a concerning procedure. We aimed to evaluate the feasibility, safety, and efficacy of performing fluoroless slow-pathway cryoablation guided by the electroanatomic (EA) mapping in children and adolescents. METHODS: Twenty-one consecutive patients (mean age 13.5 ± 2.4 years) symptomatic for AVNRT were prospectively enrolled to right atrium EA mapping and electrophysiological study prior to cryoablation. Cryoablation was guided by slow-pathway potential and performed using a 4-mm-tip catheter. RESULTS: Sustained slow-fast AVNRT was inducible in all the patients with a dual AV nodal physiology in 95%. Acute success was achieved in 100% of the patients with a median of two cryo-applications. Fluoroless ablation was feasible in 19 patients, while in two subjects 50 seconds and 45 seconds of x-ray were needed due to difficult progression of the catheters along the venous system. After a mean follow-up of 25 months, AVNRT recurred in five patients. All the recurrences were successfully treated with a second procedure. In three patients, a fluoroless cryoablation with a 6-mm-tip catheter was successfully performed, while in the remaining two patients, a single pulse of 60 seconds of radiofrequency energy was applied under fluoroscopic monitoring. No complications occurred. CONCLUSIONS: Combination of EA mapping systems and cryoablation may allow to perform fluoroless slow-pathway ablation for AVNRT in children and adolescents in the majority of patients. Fluoroless slow-pathway cryoablation showed a high efficacy and safety comparable to conventional fluoroscopy guided procedures.