A 22-year-old man was found dead in his room, lying on his bed, with a kitchen knife embedded in his thorax. The external examination revealed only 1 deep incised horizontal wound in the third left intercostal space beside the sternum. There were no hesitation marks or defense injuries. On both flexor sides of the wrists, the forearms, and the arms and on the right and the left side of the neck, there were several old transversal cut scars. At the autopsy, once the single-edged knife was removed, and after a median sternotomy, the penetration depth of the stab wound revealed an incision of the left pleura, the pericardium, and the transfixed heart, from the anterior to the posterior side, ending on the seventh thoracic vertebra. Toxicological screening resulted as negative. Death occurred as a result of hemorrhagic shock after deep myocardial injuries. A psychiatric history of paranoid schizophrenia; the old scars, which were marks of previous attempted suicides; and the position of the weapon suggested that it was a suicide caused by a single strong stab wound in the cardiac region. This unusual manner of self-stabbing with a single stab to the heart without hesitation wounds was important to exclude other causes of death.