Clinical judgement is not sufficient for the management of conduction defects (indications for diagnostic electrophysiologic studies)

Although analysis of the surface electrocardiograms is usually sufficient in the diagnosis and management of patients with cardiac arrhythmias, electrophysiologic studies can improve diagnostic, therapeutic, and prognostic decisions. Indications for electrophysiologic studies appear to include the following: asymptomatic patients with chronic second degree AV block, both type I and type II with or without bundle branch block, asymptomatic patients with complete AV block; symptomatic patients with bundle branch block and 1:1 AV conduction; patients with bundle branch block complicating acute myocardial infarction; patients with electrocardiograms suggesting pseudo AV block; symptomatic patients with sinus bradycardia, in whom the causal relationship is not clear enough to justify pacing therapy; patients with with Wolff-Parkinson-White syndrome and frequent paroxysmal supraventricular tachycardia; patients with recurrent paroxysmal ventricular tachycardia; and patients with syncope or severe dizziness in whom the causal mechanism is not defined.