Signal-averaged ECG (SAECG) - Arrhythmic risk stratification
The signal-averaged electrocardiogram (SAECG) is a noninvasive signal-processing technique to detect subtle abnormalities in the surface ECG, not visible to the naked eye.
The SAECG uses computerized averaging of ECG complexes during sinus rhythm to facilitate the detection of small microvolt-level signals, which occur later than rapid ventricular or atrial activation and are termed late potentials.
These late potentials represent delayed ventricular or atrial activation, which may reflect the presence of myocardial scar tissue and identify patients at increased risk for tachyarrhythmias.
The SAECG has been studied in an effort to identify individuals at risk for Sudden Cardiac Death (SCD) with cardiomyopathies of various aetiologies, particularly in the context of ischemic cardiomyopathy, arrhythmogenic right ventricular dysplasia and Brugada syndrome.
The SAECG has no contraindications.
The SAECG has no risks.
The execution of this exam does not include preparation rules.
A resting electrocardiogram (ECG) is recorded in the supine position using an ECG machine equipped with SAECG software.
Unlike standard basal ECG recording, which requires only a few seconds, SAECG recording requires a few minutes (usually about 7-10 minutes), as the machine must record multiple subsequent QRS potentials to remove interference due to skeletal muscle and to obtain a statistically significant average trace. For this reason, it is important for the patient is as still as possible during the recording.