The short and medium term effects of Endovascular Aneurysm Repair (EVAR) on coagulation, fibrinolysis and renal function in patients with Abdominal Aortic Aneurysms

Background: Previous reports described activation of the haemostatic mechanism in patients with abdominal aortic aneurysm (AAA). Both open and endovascular repair of AAA affect the haemostatic markers. Cystatin C is sensitive endogenous marker of renal function that is strongly associated with cardiovascular outcomes. Aim: To establish the medium-term effects of endovascular and open aneurysm repair on coagulation, fibrinolysis and renal function. Patients and Methods: Twenty-nine patients completed twelve months follow-up after EVAR, eleven patients were recruited after they had open aneurysm repair and eight age-matched control were recruited. Patients were tested for markers of coagulation, fibrinolysis and renal function pre-operatively and at 1, 6 and 12 months post-operatively. Results: Pre-operatively, PF1+2 levels were significantly higher in patients with AAA. PF1+2 levels post-EVAR and post-OAR were significantly lower than pre-operative values and similar to AMC. There was no significant difference in TAT, PAI, or t-PA between AMC, AAA preoperatively, and post-EVAR. Post-OAR, PAI activity was significantly higher than pre-operatively. 24 hours after procedure, a significant increase in Cystatin C and serum creatinine (sCr) and significant decrease in eGFR were seen. Cystatin C increased significantly at 1, 6 and 12 months. Conclusion: AAA is associated with increased thrombin generation without up-regulation of fibrinolysis. The pro-thrombotic, hypo-fibrinolytic diathesis returns toward normal in the medium term after EVAR and OAR. EVAR is associated with a significant increase in Cystatin C 24 hours after the procedure and is maintained for 12 months. sCr and eGFR show significant change at 24 hours.