Asymptomatic complete atrioventricular block in a 13-year-old girl.

Atrioventricular (AV) block is a delay or an interruption in the transmission of an impulse from atria to ventricles due to an anatomic or a functional impairment in the conduction system. Atrioventricular block may be congenital or acquired. Electrocardiographic screening of asymptomatic school-aged children (median, 12.