Catheter Ablation for SVT in Children < 15 kg and < 5 Years Old: A Systematic Review

Catheter ablation for supraventricular tachycardia (SVT) in children is technically challenging, and outcomes in children younger than 5 years and weighing less than 15 kg remain poorly characterised. No systematic review has previously focused exclusively on this population. We searched PubMed, Embase, the Cochrane Library, and ScienceDirect from January 2000 to December 2025 for studies reporting catheter ablation outcomes for SVT in children aged < 5 years and weighing < 15 kg. Risk of bias was assessed using the ROBINS-I tool. A narrative synthesis was performed due to clinical and methodological heterogeneity. The protocol was registered on PROSPERO (CRD420251207901). Ten retrospective cohort studies comprising 128 patients undergoing 154 procedures were included. Acute procedural success was high across all studies, with an overall mean of approximately 94% (range 75-100%). Recurrence rates ranged from 0% to 20%, with most studies reporting low or no recurrence. Complication rates varied widely (0-32%); three studies reported no complications, while others documented events including vascular injury, transient conduction disturbances, and structural complications. In carefully selected children aged < 5 years and weighing < 15 kg, catheter ablation for SVT achieves high acute success rates comparable to older paediatric populations, with an acceptable but variable complication profile. These findings may support consideration of ablation in this high-risk group, challenging rigid weight-based thresholds that may delay definitive therapy. Prospective multicentre studies are needed to define optimal patient selection criteria and generate higher-quality evidence.