Subendocardial hemorrhages in a case of complete avulsion of the heart

We present a case of a 66-year-old man who died on the scene in a traffic accident. He was a car driver involved in a head-on collision with a bus. Autopsy performed 4 days after death showed multiple head, torso, and limb injuries, including complete avulsion of the heart from the great vessels and avulsion of both lungs from the tracheobronchial tree due to rapid deceleration. Gross examination of the heart was remarkable for patchy hemorrhages beneath the endocardium involving the left side of the interventricular septum and papillary muscles. Histological examination identified streaky subendocardial hemorrhages and perivascular hemorrhages in the subendocardial myocardium. Since the death, in this case, was instantaneous, the most likely mechanism of subendocardial hemorrhages involved a precipitous decrease in left ventricle pressure, as it is improbable that the timeline of events allowed for a catecholamine surge to occur and take effect. Findings in this case also suggest that subendocardial hemorrhages are an indicator of intravital trauma and that the time required for them to develop is very short.