Signal Averaged Electrocardiogram

What Is a Signal-Averaged Electrocardiogram?

An electrocardiogram (ECG or EKG) is one of the simplest and fastest procedures used to evaluate the heart. Electrodes (small, plastic patches) are placed at certain locations on the chest, arms, and legs.

When the electrodes are connected to an ECG machine by lead wires, the electrical activity of the heart is measured, interpreted, and printed out for the physician's information and further interpretation.

A signal-averaged electrocardiogram is a more detailed type of ECG. During this procedure, multiple ECG tracings are obtained over a period of approximately 20 minutes in order to capture abnormal heartbeats which may occur only intermittently.

A computer captures all the electrical signals from the heart and averages them to provide the physician more detail regarding how the heart's electrical conduction system is working.

Signal-averaged ECG is one of several procedures used to assess the potential for dysrhythmias/arrhythmias (irregular heart rhythms) in certain medical situations.

Other related procedures that may be used to assess the heart include:

Related procedures

Related (non-echocardiographic) procedures that may be used to assess the heart include:

• Cardiac catheterization
• Chest X-ray
• Computed tomography (CT scan) of the chest
• Echocardiogram
• Electrophysiological studies
• Holter monitor
• Magnetic resonance imaging (MRI) of the heart
• Myocardial perfusion scans
• Radionuclide angiography
• Resting or exercise electrocardiogram (ECG or EKG)
• Ultrafast CT scan