Intra‐Hisian Wenckebach after surgical closure of conoventricular ventricular septal defect.

We report a 5‐year‐old girl with transient complete atrioventricular (AV) block following surgical closure of a symptomatic conoventricular ventricular septal defect (VSD) which recovered on post‐operative day 9. She later presented with exertional dizziness and fatigue. While congenital cardiac defect repairs are occasionally complicated by complete heart block, this patient was found to have intra‐Hisian Wenckebach which is rare in the pediatric population and can be very difficult to discern from surface electrocardiograms and by Holter monitoring. Mechanisms of post‐surgical AV block, including intra‐Hisian Wenckebach, are not well characterized in the pediatric population. [ABSTRACT FROM AUTHOR]