chapter  11
10 Pages

Evaluation of hypercoagulable states and molecular markers of acute venous thrombosis

WithDiane M. Nitzki-George, Joseph A. Caprini

Vessel injury, venous stasis, and thrombophilias favor thrombosis. The risk of venous thromboembolism (VTE) increases in proportion to the presence of these predisposing risk factors. Elevated D-dimer is not necessarily a risk factor causing VTE, but it should be used and interpreted as a marker of hypercoagulability. The degree of D-dimer elevation with VTE may depend on the extent of disease, the duration of symptoms, and the use of anticoagulants, with lower D-dimer levels being associated with less extensive disease, longer duration of symptoms, and anticoagulant use. The combination of a genetic thrombophilic defect and one or more acquired risk factor(s), such as surgery or oral contraceptive use, lead to a higher risk of VTE than the separate effects of these single factors. Antibody syndrome is an antibody-mediated hypercoagulable state, defined by the combination of clinical and pathological characteristics as detailed by the Sydney classification.