P. J. Lawson1, H. B. Moore1, E. E. Moore1, M. E. Gerich1, G. R. Stettler1, A. Banerjee1, J. A. Schoen1, R. D. Schulick1, T. L. Nydam1 1University Of Colorado Denver,Aurora, CO, USA
Introduction:
Elevated clot strength (MA) measured by thrombelastography (TEG) is associated with thrombotic complications. However, it remains unclear how MA translates to thrombotic risks, as this measurement is independent of time and blood flow. We hypothesize that under flow conditions, increased clot strength correlates to time dependent measurements of coagulation.
Methods:
Surgical patients at high risk of thrombotic complications were analyzed with TEG and T-TAS (Total Thrombus-formation Analysis System). TEG hypercoagulability was defined as an R<11.2min, Angle>49, MA>60 or LY30<0.9% (based off of healthy control data, n=160). The platelet chip (PL) of T-TAS was used to measure clotting at arterial shear rates. PL measurements include: occlusion time (OT), occlusion speed (OSp), and total clot generation [area under the curve (AUC)]. These measurements were correlated to TEG indices.
Results:
Thirty patients were analyzed. 56% had TEG detected hypercoagulability based on R, 63% angle, 73% MA, and 64% LY30. When correlated to PL chip output, only the MA significantly correlated to OT (Rho -0.418 p=0.022), OSp (Rho 0.446 p=0.014), and AUC (Rho 0.439 p=0.015). Hypercoagulability defined by MA was associated with significantly decreased OT (4:06 min vs 6:42 p=0.016), faster OSp (21 kPA/min vs 11 p=0.014), and increased clot generation (AUC 430 kPKA*min vs 350 p=0.035). Other TEG variables were not associated with PL measurements.
Conclusion:
Clot strength measured by TEG correlates to flow measured coagulation changes, and is consistent with clinical data implicating MA with thrombotic events. This in vitro data supports feasibly using MA or T-TAS PL to guide the treatment of hypercoagulability with antiplatelet medication, and warrants prospective evaluation.