ARVC

Arrhythmogenic right ventricular cardiomyopathy (formerly arrhythmogenic right ventricular dysplasia) is an inherited condition of fibrofatty deposition in the RV that causes RV dysfunction and conduction abnormalities (with predisposition to ventricular arrhythmias). It is the second most common cause of sudden cardiac death in young people and more commonly found in those of Mediterranean descent.

The EKG findings may include epsilon wave, T wave inversion in V1-V3, prolonged S wave upstroke in V1-V3, localized QRS widening in V1-V3, and paroxysmal VT with LBBB morphology. The epsilon wave is a positive deflection found at the end of the QRS complex and is the most specific finding. These can be very subtle and some advocate increasing the amplitude and speed of the strip to improve detection of epsilon waves. They represent myocytes that have delayed excitation as they are surrounded by fat cells, causing the conduction to these myocytes to be delayed. Prolonged S wave upstroke causes a more flat ascending limb of the S wave, usually into a downsloping ST segment that is depressed. This commonly causes localized QRS widening. These also represent areas of delayed conduction in the RV due to the fibrofatty deposition, but the delay is somewhat smoother than in epsilon waves. The T wave inversions in these leads represent repolarization abnormality. ARVC causes VT with LBBB morphology as it originates from the right ventricle (therefore, goes through right ventricle before left ventricle, producing LBBB morphology).

Examples:

Further Reading:

https://litfl.com/arrhythmogenic-right-ventricular-cardiomyopathy-arvc/

https://litfl.com/epsilon-wave-ecg-library/

http://hqmeded-ecg.blogspot.com/search/label/Arrhythmogenic%20Right%20Ventricular%20Cardiomyopathy