D-dimer generally refers to D-dimer, which is the degradation product of cross-linked fibrin. high D-dimer represents acute thrombosis or hypercoagulability in the body, which is commonly seen in cardiac and cerebral infarction, deep vein thrombosis of the lower limbs, DIC and other diseases. 1. Cardio-cerebral infarction: Cardio-cerebral infarction is commonly caused by the formation of blood clots in cardiovascular and cerebral vessels, blocking the normal blood supply of cardiovascular and cerebral tissues, resulting in hypercoagulability of the blood, which leads to the elevation of D-dimer. 2. Lower extremity deep vein thrombosis: patients who undergo surgery or are bedridden for a long period of time, due to stagnation of venous blood flow, deep vein thrombosis is formed in the lower extremity, which also often leads to elevated D-dimer. 3. DIC: DIC, also known as disseminated intravascular coagulation, refers to the activation of coagulation factors in the body on the basis of certain serious diseases, and the emergence of microvascular thrombosis throughout the body, resulting in circulatory failure and shock. the whole body’s fibrinolytic system is hyperactive in DIC, and therefore D-dimer will be elevated. D-dimer is not a specific indicator, but only shows the body’s high coagulation, high fibrinolytic state, clinical diagnosis of the disease also need to be combined with other manifestations of specific analysis, comprehensive judgment. If you have a high D-dimer, it is recommended that you consult a doctor in time to avoid delaying your condition.