Normally, stable venous thrombosis does not affect normal life. When a venous thrombus dislodges, it may cause a blockage of a blood vessel, leading to diseases such as cerebral infarction and myocardial infarction. Venous thrombosis is the result of platelet activation and coagulation factors being activated, leading to clotting of blood in the veins. Newly formed venous thrombus is usually attached to the wall of the venous blood vessel, and if it is stable and not dislodged, there are usually no obvious symptoms. A portion of the thrombus is gradually softened and dissolved by the action of fibrinolytic enzymes. When the activity of the fibrinolytic enzyme system is insufficient and the thrombus exists for a longer period of time, mechanization can occur, and the thrombus and the vessel wall are tightly adhered and no longer fall off. Prolonged presence of thrombus can occur calcium salt deposition, calcification, the formation of vein stone. Generally does not affect normal life. When the thrombus is dislodged, it can flow with the blood and reach all kinds of important blood vessels in the whole body, causing vascular blockage and leading to ischemia and hypoxia of local tissues, such as thrombus caused by cerebral vascular obstruction, causing cerebral infarction, causing coronary artery vascular blockage, which can cause myocardial infarction. Dislodgement of thrombus may cause more serious clinical symptoms, such as hemiplegia, aphasia, panic, chest pain, etc., affecting normal life. When venous thrombosis occurs, it is recommended to consult a doctor in time and standardize the treatment.