Thromboembolic disease, which includes DVTs, PEs, and their associated medical complications, affects more than 600,000 people in the United States each year and generates approximately $10 billion in medical expenditures. Similarly, a thrombus that originates as a deep venous thrombosis (DVT) in the large veins of the lower extremities may embolize to the lungs, resulting in pulmonary embolism (PE) or infarction. For example, thrombi that originate in the heart can embolize and become lodged in the small vessels of the brain, leading to a stroke or transient ischemic attack. This process is called thromboembolization. Arterial and venous systems can develop thrombi, which may cause local obstruction with associated ischemic symptoms but may also break off, or embolize, into the circulation and become lodged in distant vessels. Formation of a blood clot, or thrombus, is essential to prevent bleeding in the event of vascular injury however, inappropriate thrombus formation can cause significant morbidity and mortality. The hemostatic system acts to coordinate the delicate balance between bleeding and clot formation. D-dimer assays should also be validated in clinical studies, have established cut-off values, and reported according to the reagent manufacturers recommendations.īlood coagulation, venous thromboembolism, venous thrombosis, pulmonary embolism, D-dimer testing, fibrinogen degradation products, point-of-care testing, immunoassay, chemiluminescent immunoassay, disseminated intravascular coagulation, coronary artery disease, heart disease, cancer These include consideration of preanalytical variables and interfering substances, as well as patient drug therapy and underlying disease. In view of the diversity of D-dimer assays used in central laboratory and point-of-care settings, several caveats must be taken to assure the proper interpretation and clinical application of the results. Recently, a number of rapid, point-of-care D-dimer assays have been developed for acute care settings that utilize a variety of methodologies. The enzyme-linked immunosorbent assay (ELISA) is the reference method for D-dimer analysis in the central clinical laboratory, but is time consuming to perform. Modern assays for D-dimer are monoclonal antibody based. D-dimer analysis is critical for the diagnosis of deep vein thrombosis, pulmonary embolism, and disseminated intravascular coagulation. D-dimers are formed by the breakdown of fibrinogen and fibrin during fibrinolysis.