TEG platelet mapping™ assay

TEG (Heamoscope Corporation, Niles, IL) is a noninvasive assay that tests platelet function [28]. Different agonists and anticoagulant venous blood samples were placed into a special cup. The concentration of the activator added to the whole blood was 1 mmol/L AA or 2 mmol/L ADP. A special cup containing venous blood was rotated at 4° 45′, with each rotation lasting 10 s. The fibrin-platelet complex cohered to the cup, and the rotary torque of the cup was transferred to the pin immersed in the blood sample. The rotation of the pin was converted to electrical signals by electromechanical sensors, which were monitored by a computer. Maximum amplitude (MA) directly reflects the maximal clot strength that facilitates the formation of the cross-linked fibrin clot. The MA of the cyclooxygenase-1 pathway and P2Y12 was measured as MA_AA and MA_ADP, respectively. We defined a<50% and<30% inhibition of AA- and ADP-induced clot formation (i.e., TEG-AA inhibition, TEG-ADP inhibition [ADPI]) as HOPR-AA and HOPR-ADP, respectively [6, 29]. AA/ADPI was calculated using the following formula: