Long QT syndrome with AV Wenckebaching & bundle branch block in a neonate

Abstract

We present a case of 21-day-old neonate brought with history of 3 episodes of syncope. Evaluation revealed congenital long QT syndrome associated with long cycle atypical AV Wenkebaching with a long short cycle sequence related left bundle branch aberrancy. Syncope was attributed to multiple episodes of Torsades de Pointes, necessitating emergency epicardial pacemaker implantation. In addition, child was started on oral propranolol therapy. On 2 months follow up, child was stable with no ventricular high rate episodes during pacemaker interrogation.

Calmodulin mutation in long QT syndrome 15 associated with congenital heart defects further complicated by a functional 2:1 atrioventricular block: Management from foetal life to postpartum

“…An alternative explanation could be a ‘true’ AV nodal block with an associated long QTc due to damage to the AV node and myocardial ion channels by anti-Ro antibodies [ 19 ]. In the present case, this last hypothesis was excluded by the transoesophageal EP study and the absence of anti-Ro antibodies in the mother.…”