Lower extremity deep vein thrombosis is a common disease in the venous system. Once the embolus is dislodged, it can enter and block the pulmonary artery with blood flow, causing pulmonary embolism. Patients suddenly experience unexplained chest pain, cough, dyspnea, deficiency, pallor, cold sweat, etc., and have symptoms of cerebral hypoxia such as extreme anxiety, lethargy, nausea, convulsions and coma, etc. Sudden death can occur in severe cases. To avoid fatal pulmonary embolism, a device (inferior vena cava filter) can be implanted in the DD inferior vena cava, which is a necessary route for the embolus to enter the pulmonary artery, to effectively prevent the embolus from reaching the pulmonary artery and causing pulmonary embolism. Currently, the inferior vena cava filter is a relatively mature interventional procedure that is of great significance in preventing pulmonary embolism in high-risk patients.