ABSTRACT
Hypercoagulable states as a cause of acute arterial or venous thrombosis pose a difficult clinical problem. There are essentially four clinical situations in which such states occur: three involving the arterial system and one the venous system. The first is a sudden unexplained thrombosis of medium-to large-size arteries of either the upper or the lower extremity, which on occasion can involve renal, mesenteric, and cerebral vessels. The second situation, which is of particular concern to vascular surgeons, is the acute thrombosis of an arterial repair in the perioperative period. These problems are usually evident in the operating room, and all occur in the first 12 hours following surgery. The third situation is thrombosis of arterial repair at a time remote from the vascular reconstruction, which is the most uncommon occurrence. Finally, there is the sudden, unexplained episode of venous thrombosis, which can affect any and all parts of the venous circulation but most typically involves the lower extremities and on occasion also the upper extremities and the mesenteric venous circulation.
