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Determination of the Procoagulant Activity of Extracellular Vesicle (EV) Using EV-Activated Clotting Time (EV-ACT)
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Laboratory evaluation of hypercoagulability

Bernard Khor1, Elizabeth M Van Cott

  • 1Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Jackson 235, 55 Fruit Street, Boston, MA 02114, USA.

Clinics in Laboratory Medicine
|August 12, 2009
PubMed

This discussion considers several important hypercoagulable states that predispose patients to venous, and in some instances, arterial thrombosis, focusing on activated protein C resistance/factor V Leiden, prothrombin G20210A, deficiencies of protein C, protein S or antithrombin, and antiphospholipid antibodies. The discussion includes the incidence of each hypercoagulable condition, the magnitude of the thrombotic risk it poses and synergistic interactions among the various hypercoagulable conditions. Salient advances in understanding the molecular pathogenesis of each condition are presented and discussed in the context of the interpretation and clinical utility of current laboratory testing and identifying potential targets of future testing. Finally, recommendations for laboratory testing are summarized.

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