New cardiovascular technologies: Signal-averaged electrocardiography

Signal-averaged electrocardiography is a new noninvasive technique by which low amplitude signals from the heart can be detected on the body surface. By enabling the detection of late potentials, which are markers for an arrhythmic substrate, patients with high risk for arrhythmic events can be identified. Improved identification of patients at risk for arrhythmic events and sudden cardiac death is important to tailor therapy for the prevention of such events. This paper reviews the principles of signal-averaged electrocardiography and its role in identifying patients at high risk for lethal tachyarrhythmias.