Regular broad complex tachycardia in a patient with Ebstein's anomaly

Ebstein's anomaly (EA) is an uncommon congenital heart disease characterized by apical displacement of the tricuspid valve and atrialization of the right ventricle (RV). EA is associated with accessory pathways, especially right-sided, often multiple, providing a substrate for supraventricular tachycardia (SVT). Stretching and fibrosis of the right atrium and dysplastic RV provides additional substrates for other atrial and ventricular tachyarrhythmias. Differentiating preexcited antidromic tachycardia from ventricular tachycardia can be quite challenging, especially where there are no cardiac electrophysiology services. We present a case of regular broad complex tachycardia in a 1-year-old child admitted with heart failure.