Extrapericardial cardiac tamponade secondary to traumatic hemorrhage of the thymus

This report describes a 90-year-old man who sustained blunt chest trauma that progressed to circulatory failure from an enlarging anterior mediastinal hematoma. Emergent sternotomy was performed, revealing a hematoma primarily involving the thymus that was promptly evacuated. Extrapericardial cardiac tamponade is an uncommon event that occurs when fluid collects within the mediastinum but outside the pericardium. Hemodynamically significant hemorrhage of the thymus is rare because the gland begins to involute early in development. To our knowledge, cardiac tamponade secondary to traumatic hemorrhage of the thymus has not been previously described. Early recognition and hematoma evacuation can be lifesaving.