ABSTRACT
Ventricular arrhythmias in the structurally normal heart (SNH), sometimes referred to as “idiopathic ventricular arrhythmias,” represents a much higher percentage of overall VAs in children compared with adults. Although non-sustained VAs in children often do not cause symptoms, palpitations, light-headedness, or chest pain may be present. Greater than 80% of these VAs arise from the RV or LV OT (including from the aortic and pulmonic valve cusps), with the remainder arising from a papillary muscle, TV or MV annular component, or epicardial regions of the LV summit or cardiac crux. Whereas most VAs in children are premature ventricular contractions (PVCs) or nonsustained VT, FVT, usually caused by macroreentry involving the posterior (most commonly) or anterior LV fascicle, is an important form of sustained VT. Pharmacological therapy in the form of antiarrhythmic drugs is often ineffective in the suppression of VAs in children, and they require long-term use in an otherwise healthy population. Recent advances in electroanatomical mapping (EAM) and multimodal imaging on one hand and improvements in ablation catheters and energy sources on the other have improved the safety and effectiveness of ablation procedures. Therefore, even in older children, catheter ablation is currently considered as a first line measure when treatment is felt to be appropriate. Finally, with increased understanding of the mechanisms and anatomical substrates of entities leading to polymorphic VT, including such genetic disorders as Brugada syndrome, potentially curative approaches by way of catheter ablation may now be considered in children and young adults, although cardiac implantable electronic device therapy is still considered first-line.
