Evaluation of the Platelet Mapping Assay on rotational thromboelastometry ROTEM.

Rotational thromboelastometry ROTEM is available as point-of-care coagulation monitoring in an increasing number of European operating theatres and emergency rooms. The Platelet Mapping Assay has been described as a platelet aggregation assay for thromboelastography TEG. The aim of this experimental trial was to evaluate feasibility of the Platelet Mapping Assay on the ROTEM test system. Whole blood was drawn from 22 adult volunteers and patients with and without antiplatelet medication. Platelet aggregability was determined in three whole blood assays: the Platelet Mapping Assay using both activators arachidonic acid (AA) and adenosine diphosphate (ADP) on TEG, its adapted version on ROTEM, and the multiple electrode impedance aggregometer Multiplate. Percent aggregation inhibition results were plotted in a linear regression analysis and correlation was estimated. Sensitivity and specificity for detecting antiplatelet medication were determined. Overall correlations were statistically significant with an r(2) = 0.83 in AA-activated and an r(2) = 0.82 in ADP-activated Platelet Mapping Assay. AA-activated tests and the Multiplate analysis identified aspirin-inhibition in 86% and 100%, respectively. ADP-activated tests and the Multiplate analysis identified clopidogrel-inhibition in 67% and 89%, respectively. Specificity was low both in ROTEM and TEG. Differences in frequency distribution between the results obtained in ROTEM and TEG were not statistically significant. The Platelet Mapping Assay can be performed on the ROTEM. For the perioperative scenario, however, longer test duration and higher costs have to be considered compared to Multiplate analyses.