Epsilon waves are small deflections seen in the ST segment of leads V1 through V4 on an ECG. They are caused by delayed excitation of right ventricular myocytes. Epsilon waves are the most specific finding for arrhythmogenic right ventricular dysplasia (ARVD), a condition where right ventricular myocytes are replaced by fat. This replacement of myocytes by fat causes conduction delays in the right ventricle, producing the small epsilon wave deflections. Epsilon waves have also been seen in other conditions that cause right ventricular conduction delays or infiltration, such as infarction or sarcoidosis. Placement of Fontaine leads increases the sensitivity of detecting epsilon waves compared to standard ECG lead placement.

1. EPSILON WAVE
Dr.G.VENKATA RAMANA
MBBS DNB FAMILY MEDICINE

2. DEFINITION
• Small deflection (“blip” or “wiggle”) buried in the
end of the QRS complex
• On Standard 12-lead ECG (S-ECG), best seen
in ST segment of V1 and V2, they are usually
present in leads V1 through V4
• Caused by post-excitation of myocytes in the
right ventricle
• Characteristic finding in patients
with arrhythmogenic right ventricular
dysplasia (ARVD)

3. Epsilon wave in V1 due to RV conduction delay

4. • Epsilon waves are the most specific and characteristic
finding in arrhythmogenic right ventricular
dysplasia (ARVD)
• In ARVD, myocytes are replaced by fat, producing
islands of viable myocytes in a sea of fat
• This causes a delay in excitation of some of the
myocytes of the right ventricle, producing a small “blip”
seen during the ST segment of the ECG
• Epsilon waves have also been described in patients
with:
• Posterior myocardial infarction
• Right ventricular infarction
• Infiltrative disease
• Sarcoidosis

5. ECG Examples of Epsilon Waves

8. Fontaine lead
Comparison of S-ECG versus F-ECG in the ability to detect epsilon waves (arrows)
The Fontaine lead placement increases sensitivity of detecting epsilon
waves so that they are detected in three leads (FI, FII, FIII) rather than one
lead in the regular placement