Blood coagulation and fibrinolytic response after endovascular stent grafting of thoracic aorta.

Abstract

Thrombosis is common in aneurysms immediately after stent-grafting, because of exclusion from systemic blood flow. We studied changes in blood coagulation and the fibrinolytic system in patients with thoracic aortic aneurysm or dissection after stent-grafting to examine risk for consumption coagulopathy. Thirty-one thoracic aortic aneurysms were treated with stent-grafting (aneurysm group), and 29 aortic dissections were treated with entry closure with stent-grafting (dissection group). The stent-graft was constructed from a self-expanding Z stent and thin-walled woven polyester fabric. Platelet count, fibrinogen, antithrombin III (AT III), and thrombin-AT III complex were assayed as markers of coagulation. Plasminogen, alpha(2)-plasmin inhibitor, alpha(2)-plasmin inhibitor-plasmin complex, fibrin degradation products fragment E (FDP-E), and fibrin degradation products d-dimer were monitored as markers of fibrinolysis. Blood samples were collected before surgery and on postoperative days 1, 3, 7, and 14. In both groups platelet count significantly decreased on postoperative days 1 and 3, and increased on postoperative day 14. AT III significantly decreased on postoperative day 1, but recovered after postoperative day 7. FDP-E significantly increased on postoperative day 1 in both groups. There was significant correlation of aneurysm diameter with alpha(2)-plasmin inhibitor-plasmin complex, fibrin degradation products, and d-dimer in the dissection group on postoperative day 1. Activation of coagulation and fibrinolysis was observed after stent-grafting to treat thoracic aortic aneurysm and aortic dissection. However, no patients exhibited consumption coagulopathy postoperatively. Therefore we believe there is little risk for consumption coagulopathy after stent-grafting.