Characterisation and reproducibility of a human ex vivo model of thrombosis

Abstract Background The Badimon chamber is a clinical ex vivo model of thrombosis that mimics flow conditions within the coronary circulation of man. The aims of this study were to characterise thrombus formation in the chamber and evaluate its reproducibility. Methods Using blood from 24 healthy human volunteers, thrombus formation was assessed at low and high shear rates with porcine aortic tunica media as the thrombogenic substrate. Thrombus area was measured histomorphometrically. Reproducibility was assessed by paired measurements made both within and between days. Platelet activation was assessed before and at selected points within the extracorporeal circuit using flow cytometry, and fibrin content and distribution within the thrombus were assessed by immunohistochemistry. Results Total thrombus area was highly reproducible within and between days in the low shear ([mean thrombus area, mean difference ± SEM] 8,018 μm 2 , 58 ± 204 μm 2 and 8,177 μm 2 , -154 ± 168 μm 2 respectively) and high shear chambers (11,802 μm 2 , -52 ± 175 μm 2 and 11,877 μm 2 , 220 ± 181 μm 2 respectively). Total thrombus area was greater in the high compared to the low shear chamber (11,970 ± 285 μm 2 versus 7,892 ± 298 μm 2 ; P  versus 8.3 ± 1.6%, P  Conclusions The Badimon chamber provides a highly reproducible technique for the assessment of ex vivo platelet-rich thrombus formation in man.