Changes in thrombin generation, fibrinolysis, platelet and endothelial cell activity, and inflammation following endovascular abdominal aortic aneurysm repair

BACKGROUND: Abdominal aortic aneurysm (AAA) is a chronic inflammatory condition associated with a prothrombotic, hypofibrinolytic diathesis that may increase the risk of cardiovascular events. The effect of endovascular aneurysm repair (EVAR) on this prothrombotic diathesis is not fully understood, especially over the medium and long term. A better understanding of these postintervention changes may improve the risk of cardiovascular complications in the long term. The purpose of this study was to examine thrombin generation, fibrinolysis, platelet and endothelial activation, and the inflammatory response during the 12 months following EVAR. METHODS: Twenty-nine patients (mean age, 76.9 years) undergoing EVAR for AAA (mean diameter 6.9 cm) had prothrombin fragment (PF) 1 + 2, thrombin-antithrombin complex (TAT), plasminogen activator inhibitor (PAI) activity, tissue plasminogen activator (t-PA) activity and antigen, soluble P- and E-selectin, and highly sensitive C-reactive protein (hsCRP) measured before and at 24 hours, and 1, 6, and 12 months after surgery. RESULTS: PF1 + 2 were markedly elevated prior to EVAR and remained so at 24 hours and 1 month, but had decreased significantly at 6 and 12 months. TAT was also elevated prior to EVAR and increased still further by 24 hours, but fell to below baseline levels thereafter. PAI activity and t-PA antigen were normal prior to EVAR, increased significantly at 24 hours, and then fell to baseline levels. t-PA activity was only detectable at 1 and 6 months; there was a significant rise in soluble P- and E-selectin after EVAR, which was sustained for 12 months. hsCRP increased transiently in response to EVAR but returned to preoperative levels by 1 month. CONCLUSIONS: The prothrombotic, hypofibrinolytic diathesis associated with AAA is normalized 12 months after EVAR. This beneficial systemic effect of EVAR for AAA disease may help protect patients against future thromboembolic cardiovascular events.