An unusual resolution of T-wave oversensing in an implantable cardioverter defibrillator in a child with long QT syndrome.

T-wave oversensing poses a clinical challenge often resulting in inappropriate therapies and shocks. T-wave oversensing can often be resolved by certain programmable adjustments while accepting a small risk of undersensing ventricular fibrillation. The following case depicts a girl with LQT whose transvenous defibrillator repeatedly demonstrated T-wave oversensing despite optimizing various programmable features and a separate pace/sense lead. Utilization of an LV epicardial pace/sense lead with stable R-waves affirmed an unusual resolution of T-wave oversensing and avoidance of inappropriate shocks.