Clinical Significance of Epsilon Waves in Arrhythmogenic Cardiomyopathy

Abstract

Detection of epsilon waves on 12-lead ECG reflects significant RVOT involvement, which was associated with episodes of sustained ventricular tachycardia but not sudden cardiac death.

Isolated Late Activation Detected by Magnetocardiography Predicts Future Lethal Ventricular Arrhythmic Events in Patients With Arrhythmogenic Right Ventricular Cardiomyopathy

“…This finding confirms the insensitivity of standard ECG to detect depolarization abnormalities in the lateral to inferior region of RV, which is relatively far from the precordial leads. These results are consistent with the report by Protonotarios et al 3 It should be emphasized that MCG may detect the arrhythmogenic substrate even better than invasive electroanatomic mapping, because MCG detects abnormally delayed activation irrespective of its transmural location. Identifying the location of ILA would provide significant information for planning the ablation strategy.…”

“…One is "post-excitation" epsilon waves, the hallmark of ARVC, which occurs after the end of the QRS complex at leads V1-V3, with a prevalence of approximately 20% in patients with arrhythmogenic cardiomyopathy. 1, 3 The other is alteration in the right precordial QRS duration and morphology. [16][17][18][19] Several investigators have proposed new ECG markers to better characterize delayed RV activation, including delayed S-wave upstroke at V1-3 17 and prolonged terminal activation duration.…”

“…1,2 Delayed activation within the abnormal myocardium as a substrate of ventricular tachycardia (VT) in ARVC could clinically manifest as epsilon waves on ECG or late potential (LP) depicted on signal-averaged ECG (SAECG). Protonotarios et al established the association of epsilon waves with VT. 3 However, the sensitivity of epsilon waves is low, because it may be masked within the prolonged S-wave or complete right bundle branch block (CRBBB). Similarly, SAECG cannot be used in patients…”

Arrhythmogenic cardiomyopathies (ACs): diagnosis, risk stratification and management

“…Epsilon waves defined as reproducible low-amplitude signals after the end of the QRS complex up to the onset of the T wave are detected in approximately 20%–30% of ARVC cases. They are usually present in the anterior precordial leads and can extend to inferolateral leads 59. It is important that they are strictly defined as waves separated from QRS complex by an isoelectric line to avoid misinterpretation of fragmentation in the final portion of the QRS complex 60.…”

“…It is important that they are strictly defined as waves separated from QRS complex by an isoelectric line to avoid misinterpretation of fragmentation in the final portion of the QRS complex 60. Epsilon waves have been associated with significant structural abnormalities of the RV, particularly of the RVOT 59. Signal averaged ECG is another means of detecting delayed late potentials, and it can be positive in all forms of AC as it represents fibrosis in either ventricles 61…”