Authors present the case of the sudden death of a 30-year-old man, 3 h since his hospitalization by the onset of aspecific chest pain. ECG findings revealed the presence of localized ST segment elevation in precordial leads (V1-V4) and DII-DII, and aVF mimicking acute antero-inferior myocardial infarction. A diagnosis of acute antero-inferior myocardial infarction was advanced and the patient introduced to thrombolytic therapy. Suddenly, on ECG monitor, conduction abnormalities were early recorded (ventricular extrasystole) followed by ventricular tachycardia degenerating in fatal ventricular fibrillation. An alleged medical malpractice was sued against the cardiologist. A complete immunohistochemical study was performed. Histologically, the heart presented massive interstitial lymphocytic infiltrate and focal myocytes necrosis. The diagnosis of acute lymphocytic myocarditis was established as the cause of death.