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Updated: May 23, 2026

A Microfluidic Flow Chamber Model for Platelet Transfusion and Hemostasis Measures Platelet Deposition and Fibrin Formation in Real-time
Published on: February 14, 2017
The relationship between aortic aneurysm sac thrombus volume on coagulation, fibrinolysis and platelet activity
Robert S M Davies1, Mohamed Abdelhamid, Rajiv K Vohra
1University Department of Vascular Surgery, Heart of England NHS Foundation Trust, Birmingham, UK. rsmdavies@mac.com
Aim:
Abdominal aortic aneurysm (AAA) is associated with chronic mural inflammation and a pro-thrombotic diathesis. It has been suggested that both may be related to biologically active intra-sac thrombus. The aim of this study was to examine the relationship between thrombin generation, fibrinolysis, platelet activity and AAA sac thrombus volume.
Methods:
30 patients (29 men) of median (IQR) age 75 (71-82) years with an infra-renal AAA >5.5 cm in antero-posterior diameter were prospectively studied. AAA, lumen and thrombus volumes were calculated using a CT workstation (Vitrea). Plasma thrombin-antithrombin (TAT), plasminogen activator inhibitor (PAI)-1, and soluble (s) P-selectin were measured as biomarkers of coagulation, fibrinolysis and platelet activity, respectively
Results:
Median (IQR) AAA total, lumen and thrombus volumes were 188 (147-247) cm(3), 80 (54.3-107) cm(3) and 97.6 (63-127) cm(3) respectively. TAT levels were significantly higher (median, QR, 7.15 [4.7-31.3] μg/L, p=<0.001) and sP-selectin levels significantly lower (median, IQR, 80.5 [68-128] ng/ml, p=<0.0001) than the normal range. PAI-1 levels (median, IQR, 20.9 [8.4-50.7] ng/ml) were normal. There was no correlation between AAA thrombus volume and PAI-1 (r=-0.25, p=0.47), sP-Selectin (r=0.26, p=0.43) or TAT plasma levels (r=-0.21, p=0.54).
Conclusion:
The present study confirms that patients with AAA demonstrate haemostatic derangement, but the extent of the haemostatic derangement does not correlate with AAA sac thrombus volume.
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