Electrocardiographic and electrophysiologic studies of the univentricular hearts.

Tachy- and bradydysrhythmias were found to be common in patients with univentricular hearts. They lead to considerable mortality. Intracardiac electrophysiologic studies may be used in these patients as in patients with normal hearts. It is anticipated that post surgical dysrhythmias will be at least as common after division of univentricular hearts as for more common repairs as tetralogy of Fallot.