signal-averaged electrocardiography

signal-averaged electrocardiography

A technique that amplifies late potentials (high-frequency, low-amplitude signals at the end of a QRS complex), which are attributed to fragmented and delayed conduction through the borders of a myocardial scar.
The delayed conduction of late potentials allows re-entry of electrical impulses and increased susceptibility to ventricular arrhythmias; detection of late potentials by signal-averaged electrocardiography correlates well with inducibility of ventricular tachycardia (VT). It is a useful, noninvasive test for identifying increased risk of VT, but is of little use in patients with conduction defects