Focal atrial tachycardia accounts for up to 10–15% of supraventricular tachycardiasubstrates in patients < 30 years. In this study, we aimed to demonstrate the outcome of transcatheter ablation procedures performed through three-dimensional electroanatomic mapping systems using minimal fluoroscopy in a paediatric cohort with focal atrial tachycardia.

Forty-nine consecutive patients with focal atrial tachycardia who underwent an electrophysiologic study and a transcatheter ablation procedure in our hospital from September 2014 to February 2020 were included into the study.

The mean weight of the patients was 48.63 ± 15.4 kg, and the mean age was 14.56 ± 3.5 (5.5–18.4) years. The tachycardia was defined as incessant in 26 patients. Thirteen patients had left ventricular systolic dysfunction with a mean left ventricular ejection fraction of 38.47 ± 12.4% on echocardiography. The mean procedure time was 148.7 ± 94.5 minutes. Transseptal puncture and thus fluoroscopy were required in nine patients. The mean fluoroscopy time was 4.51 ± 5.9 minutes. No fluoroscopy was needed in ablations performed in the right atrium. The acute success rate of the ablation procedures was 97.9%. The mean follow-up period was 50.71 ± 23.5 months. Recurrence was noted in two patients (4.2%).

The outcomes of three-dimensional electroanatomic mapping-guided transcatheter ablation procedures are promising with high acute success, low recurrence and complication rates in children with focal atrial tachycardia. The use of fluoroscopy can be significantly decreased with three-dimensional mapping systems in this group of patients.

Fascicular tachycardia is a common form of sustained idiopathic left ventricular tachycardia. This study aimed to achieve successful results with catheter ablation procedures performed through three-dimensional electroanatomic mapping using near-zero fluoroscopy in fascicular tachycardia patients.

In this study, we included 33 consecutive children with fascicular tachycardia, for whom we performed a transcatheter radiofrequency ablation procedure using the EnSite® system. Activation mapping was performed in all patients during tachycardia, and the earliest presystolic purkinje potentials were the target site for radiofrequency lesions.

Twenty-five patients were male, and eight were female. The mean weight of the patients was 39.6 ± 10.4 kg, and the mean age was 13.6 ± 2.5 years. The mean procedure time was 121.3 ± 44.3 minutes. The mean follow-up period was 18.4 ± 6.5 months. No fluoroscopy was needed in 30 patients. The mean fluoroscopy time in the remaining patients was 166.6 ± 80 seconds. All of the patients had left posterior fascicular tachycardia except for one who had left anterior fascicular tachycardia. The acute success rate was perfect (100%). No patients developed left bundle branch block or complete atrioventricular block. Recurrence developed in one patient.

We suggest that radiofrequency ablations via an electroanatomic mapping system are quite safe and effective, with high success rates in paediatric patients with fascicular tachycardia. This method has the advantage of avoiding ionising radiation exposure for both the patient and operator, thus reducing the lifetime risk of malignancy in the paediatric population.