From the Guidelines
An epsilon wave is a distinct low-amplitude signal, often a small positive deflection or notch, that appears between the end of the QRS complex and the onset of the T-wave in leads V1-V3 on an electrocardiogram (ECG) 1.
Characteristics of Epsilon Wave
- It is a highly specific ECG marker for Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) 1.
- The morphology of the epsilon wave can be variable but is often a broad, low-amplitude terminal QRS notch 1.
- Epsilon waves are typically observed in the anteroseptal precordial leads in patients with ARVC 1.
Clinical Significance
- The presence of an epsilon wave is a major diagnostic criterion for ARVC 1.
- ARVC is a cause of sudden death in young people and athletes, characterized by a broad phenotypic spectrum and loss of myocytes in the right ventricular myocardium, with fatty or fibrofatty replacement 1.
- The diagnosis of ARVC relies largely on familial occurrence, left bundle-branch pattern ventricular tachyarrhythmias, ECG findings of T-wave inversion in precordial leads, and epsilon waves, as well as right ventricular dilation or segmental wall motion abnormalities identified with cardiac magnetic resonance (CMR) imaging 1.
From the Research
Definition and Characteristics of Epsilon Waves
- Epsilon waves are a type of electrocardiographic abnormality that can be detected on a 12-lead ECG 2, 3, 4, 5, 6
- They are characterized by a small, low-frequency wave that appears after the QRS complex and before the T wave 2, 5
- Epsilon waves can be detected in various leads, including precordial and inferior leads 2, 5
Association with Arrhythmogenic Right Ventricular Cardiomyopathy
- Epsilon waves are a hallmark feature of arrhythmogenic right ventricular cardiomyopathy (ARVC) 2, 3, 4, 5, 6
- They are associated with right ventricular outflow tract (RVOT) involvement and increased RVOT diameter 2
- Epsilon waves can be used as a diagnostic criterion for ARVC, but their presence is not required for diagnosis 3
Detection and Diagnosis
- Epsilon waves can be detected using various electrocardiographic recording methods, including standard 12-lead ECG, right-sided precordial lead ECG, and Fontaine bipolar precordial lead ECG 5
- Exercise testing can uncover epsilon waves in asymptomatic patients with ARVC, particularly those with desmoplakin-positive ARVC 6
- The detection rate of epsilon waves can be improved by using combined electrocardiographic recording methods 5
Clinical Significance
- Epsilon waves are associated with an increased risk of sustained ventricular tachycardia 2
- They can be present in other medical conditions, including posterior myocardial infarction, right ventricular infarction, infiltration disease, sarcoidosis, Brugada Syndrome, Tetralogy of Fallot, and hypothermia 4
- Epsilon waves can be a useful tool in planning diagnostic work-up and recognizing the electrocardiographic phenotype of ARVC 3