Extracardiac thrombotic, embolic, and hemorrhagic causes of sudden death

The integrity of the vascular tree is essential to sustain life. However, blood vessels are the most vulnerable structure in the cardiovascular system, and disruption of the vasculature by occlusion (thrombosis/thromboembolism) or leakage (hemorrhage) can lead to sudden death. This review will concentrate on the extracardiac manifestations of two opposite, but intimately related, pathophysiologic processes that disturb vascular integrity: namely, thrombosis and hemorrhage. Thrombosis is a pathological process that leads to activation of the hemostatic system at an abnormal time and location. We are only just beginning to appreciate the myriad causes of thrombosis, some of which include vascular factors such as stasis and endothelial injury, as well as blood factors such as excessive coagulation, decreased coagulation inhibitors, or decreased fibrinolysis. Hemorrhage is a frequent cause of sudden death and may be attributable to blood vessel disease/rupture or to abnormalities within the blood itself that impair hemostasis. In this review, the pathophysiologic mechanisms of thrombosis/thromboembolism and hemorrhage are delineated and multiple system-specific disease entities are discussed.