D Dimer (FIA)

The D-Dimer test is used primarily to rule out the presence of a serious blood clot, such as deep vein thrombosis (DVT) or a pulmonary embolism (PE). When a blood clot forms and then begins to break down, it releases a specific protein fragment called D-dimer into the bloodstream. By measuring the levels of this fragment, healthcare providers can quickly assess whether an active clotting process is occurring. The primary value of this test lies in its high negative predictive value—meaning if your D-dimer levels are normal or low, it is highly unlikely that you have an acute blood clot, often sparing you from more invasive or expensive imaging tests like CT scans or ultrasounds.