Contemporary Advances of Leadless Pacing and Conduction System Pacing in Children With Congenital Heart Disease.

The management of bradyarrhythmias requiring permanent pacing in pediatric patients and those with congenital heart disease (CHD) remains uniquely challenging due to continuous somatic growth, complex cardiac anatomy, limited vascular access, and long-term risks associated with conventional cardiac implantable electronic devices. Traditional transvenous endocardial and surgical epicardial pacing systems are associated with high rates of lead failure, venous occlusion, infection, and ventricular dyssynchrony. Leadless pacemakers and conduction system pacing have emerged as promising alternatives that overcome many of these historical limitations. This review provides a comprehensive, updated overview of the technical principles, clinical applications, advantages, limitations, and appropriate patient selection strategies for these two innovative modalities in the pediatric and CHD population. Critical clarifications are provided regarding venous access requirements, age-adjusted interpretation of QRS duration, ventricular dyssynchrony evaluation, and indications for device therapy according to pediatric-specific guidelines rather than adult-derived criteria. Clinical decision-making is integrated into a structured framework based on age, body size, clinical symptoms, ventricular synchrony, and arrhythmic risk stratification.