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Invasive cardiac electrophysiology studies: Bradyarrhythmias


Studies of cardiac impulse formation and conduction using intracardiac catheters have helped define the mechanisms of bradyarrhythmias [1-4]. These invasive electrophysiology studies (EPS) have become a valuable clinical tool in the evaluation and management of cardiac dysrhythmias.

Significant bradyarrhythmias can be divided into two major categories, depending on the anatomic site of origin:

  • Sinus node (SN) dysfunction
  • Atrioventricular (AV) conduction disorders

This topic will review the role of invasive EPS in the diagnosis and treatment of patients with bradyarrhythmias, particularly its role in determining the need for a permanent pacemaker. An overview of cardiac electrophysiology and its role in the management of tachyarrhythmias are discussed separately. (See "Overview of invasive cardiac electrophysiology studies" and "Invasive cardiac electrophysiology studies: Tachyarrhythmias".)


EPS should be used as an adjunct to clinical history, physical examination, electrocardiography, and other noninvasive methods in the evaluation of bradyarrhythmias. (See "Diagnosis and evaluation of the sick sinus syndrome".)


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Literature review current through: Mar 2014. | This topic last updated: Nov 28, 2012.
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