The document discusses epsilon waves, small positive deflections within the QRS complex of an ECG, primarily associated with arrhythmogenic right ventricular dysplasia (ARVD) and other cardiac conditions. These waves indicate postexcitation of right ventricular myocytes due to fat replacement, causing delays in excitation and are best observed in leads V1 to V4. Additionally, the text references the use of Fontaine bipolar precordial leads to enhance sensitivity in detecting these waves.