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Ambulatory ECG monitoring

Philip J Podrid, MD, FACC
Section Editor
Peter J Zimetbaum, MD
Deputy Editor
Brian C Downey, MD, FACC


In contrast to the standard electrocardiogram (ECG), which provides a fixed picture of cardiac electrical activity over a brief duration, ambulatory ECG monitoring provides a view of electrocardiographic data over an extended period of time, thereby permitting evaluation of dynamic cardiac electrical phenomena that are often transient and of brief duration. The most common ambulatory ECG application is in the diagnosis and assessment of cardiac arrhythmias or conduction abnormalities (symptomatic or asymptomatic) or the presence of potential arrhythmias (such as in patients with syncope or presyncope), but ambulatory ECG also has a role in the assessment of prognosis and risk stratification of various cardiac populations, in the evaluation of arrhythmia therapy, and for the evaluation of silent ischemia. (See "Clinical features and treatment of ventricular arrhythmias during acute myocardial infarction" and "Silent myocardial ischemia: Epidemiology, pathophysiology, and diagnosis" and "Evaluation of heart rate variability".)

Ambulatory ECG monitoring, which can be performed using a variety of techniques for as short as 24 to 48 hours and for as long as months to years, offers the opportunity to review cardiac ECG data during normal routine activity, including any physical and psychological stresses. Ambulatory ECG monitoring for longer periods (when compared with standard ECG for a 10-second time period) is more sensitive for detecting spontaneous, often highly variable cardiac arrhythmias or conduction abnormalities [1,2].

Ambulatory monitoring, in conjunction with clinical and electrocardiographic findings, can be a useful component of the evaluation of the patient with unexplained syncope, presyncope, or palpitations. A detailed discussion of the evaluation of syncope and palpitations, including the role of ambulatory monitors, is presented separately. (See "Syncope in adults: Clinical manifestations and diagnostic evaluation" and "Overview of palpitations in adults".)


Ambulatory ECG monitoring is the most widely employed technology to evaluate a patient with symptoms suggestive of a cardiac arrhythmia or a conduction abnormality. The 1999 American College of Cardiology/American Heart Association (ACC/AHA) guidelines on ambulatory electrocardiography recommended only two indications for this approach [3]:

Unexplained syncope, near syncope, or episodic dizziness (see "Syncope in adults: Clinical manifestations and diagnostic evaluation")

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Literature review current through: Nov 2017. | This topic last updated: Mar 15, 2017.
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