Epsilon Waves in Arrhythmogenic Right Ventricular Dysplasia

The epsilon potential is a right ventricular conduction delay, and appears as a sharp deflection after termination of the QRS complex during the ST segment or upstroke of the T wave. It is seen in the right ventricular leads V1 and V2. (Fontaine named the waves ‘epsilon’ since epsilon follows delta in the
Greek alphabet.)


Right ventricular dysplasia is characterised by the displacement of myocytes by fat. This delays the excitation and depolarisation of those viable myocytes enveloped by the fatty tissue, and so leads to epsilon potentials.


The ECG changes in Arrhythmogenic Right Ventricular Dysplasia (ARVD) include:

• Epsilon wave (most specific finding, seen in 30% of patients)
• T wave inversions in V1-3 (85% of patients)
• Prolonged S-wave upstroke of 55ms in V1-3 (95% of patients)
• Localised QRS widening of 110ms in V1-3
• Paroxysmal episodes of ventricular tachycardia with a LBBB morphology

Epsilon wave in lead V1. [Source]

Epsilon Waves. [Source]

ECG of a patient with ARVD. The Epsilon wave is marked with an arrow. [Source]

The ECG is from a 21-year-old male with arrhythmogenic right ventricular dysplasia. Right bundle branch block, epsilon wave (arrow) and diffuse T wave inversion are present. [Source]

Further reading:

1. Corrado D, Biffi A, Basso C, Pelliccia A, Thiene G.  Twelve-lead ECG in the athlete: physiological versus pathological abnormalities. Br J Sports Med 2009; 43 :669-676. [PMID: 19734501] [Full text]
2. Perez Diez D, Brugada J. Diagnosis and Management of Arrhythmogenic Right Ventricular Dysplasia: An article from the E-Journal of the ESC Council for Cardiology Practice, European Society of Cardiology 2008. [ESC]