Implantable cardioverter-defibrillator (ICD) therapy is associated with an increasing number of ICD lead-related complications. We present a case of 52-year-old female treated with ICD for the post-infarction primary prophylaxis in whom inappropriate shocks were caused by lead damage manifested early by prodromal, unusual intracardiac electrogram (IEGM) artifacts. Some IEGM patterns should be considered as a potential marker of lead-related adverse events that may occur in the future