Signal‐averaged electrocardiography: Past, present, and future

Abstract

Signal‐averaged electrocardiography records delayed depolarization of myocardial areas with slow conduction that can form the substrate for monomorphic ventricular tachycardia. This technique has been examined mostly in patients with coronary artery disease, but its use has been declined over the years. However, several lines of evidence, derived from hitherto clinical data in patients with healed myocardial infarction, indicate that signal‐averaged electrocardiography remains a valuable tool in risk stratification, especially when incorporated into algorithms encompassing invasive and noninvasive indices. Such an approach can aid the more precise identification of candidates for device therapy, in the context of primary prevention of sudden cardiac death. This article reappraises the value of signal‐averaged electrocardiography as a predictor of arrhythmic outcome in patients with ischemic heart disease and discusses potential future indications.

Arrhythmic risk stratification in heart failure mid‐range ejection fraction patients with a non‐invasive guiding to programmed ventricular stimulation two‐step approach

“…Each participant in sinus rhythm underwent a resting supine 12‐lead ECG recording at 25 mm/s and a SAECG (MAC 5000 GE Medical, Milwaukee,WI, USA) by use of three X,Y,Z orthogonal bipolar leads (filter: 40‐250 Hz). Conventional criteria for the presence of late potentials were used (filtered QRS [fQRS]: ≥114 ms, low amplitude signal [LAS]: ≥38 ms, root mean square voltage [RMS]: ≤20 μV) for those with normal QRS duration, 19,24 but for patients with intraventricular conduction delay with a QRS duration ≥ 120 ms, the modified criteria (fQRS:≥145 ms, LAS:≥50 ms, RMS: ≤17.5 μV) 20 were applied.…”

Arrhythmic risk stratification in post-myocardial infarction patients with preserved ejection fraction: the PRESERVE EF study

“…. They also had an increased prevalence of late potentials and non-sustained ventricular tachycardia 35 . All these characteristics suggest that there is a critical amount of myocardial fibrosis required in order to sustain ventricular re-entry, rendering the use of imaging modalities capable of identifying and quantifying scar burden, such as cardiac magnetic resonance imaging, appealing alternatives 36 .…”

Syncope associated with supraventricular tachycardia: Diagnostic role of implantable loop recorders

“…Ambulatory ECG Holter monitoring is almost routinely used in the investigation of syncope with a rather less diagnostic yield in terms of correlating symptoms with potential arrhythmias (Gibson & Heitzman, 1984; Kühne et al., 2007; Sarasin et al., 2005). A SAECG may reveal late potentials, pointing to the presence of a ventricular reentry mechanism (Gatzoulis, Arsenos, et al., 2018). An EPS in the presence of abnormal 12‐lead, signal‐averaged and ambulatory ECG findings may identify cardiac production and conduction abnormalities or supraventricular and/or ventricular arrhythmias as potential syncope mechanisms (Gatzoulis et al., 2009).…”