D-dimers are fragments of blood clots that are created when the body breaks up a clot. In the 1990s, it became possible to test blood for D-dimer levels to help rule out a thrombosis. A higher than normal D-dimer level does not confirm a clot, but it strongly indicative. A D-dimer test is always performed if a deep-vein thrombosis, pulmonary embolism or DIC is suspected. However, high D-dimer levels can also indicate liver disease, rheumatoid arthritis, general inflammation, malignant cancer, trauma, pregnancy, recent surgery or even advanced age.