A comparison between the Plateletworks™-assay and light transmittance aggregometry for monitoring the inhibitory effects of clopidogrel

A simple and rapid point-of-care platelet function assay that guides antiplatelet responses to aspirin and clopidogrel may be of great clinical value for the individual tailoring of therapy. The Plateletworks® assay is based on single platelet counting and has been described as a promising point-of-care assay for the monitoring of the effects of the GP IIb/IIIa antagonists. However, data about its utility and reliability in monitoring the effects of thienopyridines is limited. In the present study we assessed reproducibility of the Plateletworks® assay over time. In addition, a comparison between the Plateletworks® assay and optical aggregometry was performed in a large cohort of patients on maintenance therapy with aspirin and clopidogrel. The Plateletworks® assay demonstrated a good agreement with optical aggregometry in measuring the response to clopidogrel. The results of Plateletworks® are, however, highly time dependent which implicates that measurements should be performed within 10 min.