Ambulatory ECG monitoring
- Philip J Podrid, MD, FACC
Philip J Podrid, MD, FACC
- Professor of Medicine, Professor of Pharmacology and Experimental Therapeutics
- Boston University School of Medicine
- Lecturer, Harvard Medical School
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 "Evaluation of syncope in adults" 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 :
●Unexplained syncope, near syncope, or episodic dizziness (see "Evaluation of syncope in adults")
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- Crawford MH, Bernstein SJ, Deedwania PC, et al. ACC/AHA guidelines for ambulatory electrocardiography: executive summary and recommendations. A report of the American College of Cardiology/American Heart Association task force on practice guidelines (committee to revise the guidelines for ambulatory electrocardiography). Circulation 1999; 100:886.
- Afzal MR, Gunda S, Waheed S, et al. Role of Outpatient Cardiac Rhythm Monitoring in Cryptogenic Stroke: A Systematic Review and Meta-Analysis. Pacing Clin Electrophysiol 2015; 38:1236.
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- Joshi AK, Kowey PR, Prystowsky EN, et al. First experience with a Mobile Cardiac Outpatient Telemetry (MCOT) system for the diagnosis and management of cardiac arrhythmia. Am J Cardiol 2005; 95:878.
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- Krahn AD, Klein GJ, Skanes AC, Yee R. Insertable loop recorder use for detection of intermittent arrhythmias. Pacing Clin Electrophysiol 2004; 27:657.
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- Pürerfellner H, Sanders P, Pokushalov E, et al. Miniaturized Reveal LINQ insertable cardiac monitoring system: First-in-human experience. Heart Rhythm 2015; 12:1113.
- Furukawa T, Maggi R, Bertolone C, et al. Additional diagnostic value of very prolonged observation by implantable loop recorder in patients with unexplained syncope. J Cardiovasc Electrophysiol 2012; 23:67.
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- Krahn AD, Klein GJ, Fitzpatrick A, et al. Predicting the outcome of patients with unexplained syncope undergoing prolonged monitoring. Pacing Clin Electrophysiol 2002; 25:37.
- Krahn AD, Klein GJ, Yee R, Skanes AC. Randomized assessment of syncope trial: conventional diagnostic testing versus a prolonged monitoring strategy. Circulation 2001; 104:46.
- Krahn AD, Klein GJ, Yee R, et al. Use of an extended monitoring strategy in patients with problematic syncope. Reveal Investigators. Circulation 1999; 99:406.
- Farwell DJ, Freemantle N, Sulke AN. Use of implantable loop recorders in the diagnosis and management of syncope. Eur Heart J 2004; 25:1257.
- Brignole M, Sutton R, Menozzi C, et al. Early application of an implantable loop recorder allows effective specific therapy in patients with recurrent suspected neurally mediated syncope. Eur Heart J 2006; 27:1085.
- Edvardsson N, Frykman V, van Mechelen R, et al. Use of an implantable loop recorder to increase the diagnostic yield in unexplained syncope: results from the PICTURE registry. Europace 2011; 13:262.
- TYPES OF AMBULATORY ECG MONITORING
- Continuous ambulatory ECG (Holter) monitors
- - Holter monitor report
- Event (loop) monitors
- - Event monitor report
- Implantable loop recorder
- - ILR report
- DIAGNOSTIC EFFICACY
- OUR APPROACH TO CHOOSING AN AMBULATORY ECG MONITORING STRATEGY
- When to choose continuous ECG (Holter) monitoring
- When to choose event monitoring
- When to choose implantable loop recording
- Other scenarios
- FOLLOW-UP AFTER AMBULATORY ECG MONITORING
- SUMMARY AND RECOMMENDATIONS