Brain stent failure may lead to aggravation of cerebral infarction, cerebral hemorrhage, thrombosis or embolism in other parts of the body, which can be directly life-threatening. 1. Cerebral infarction: if the brain stent fails, it means that the original cerebral infarction has not been lifted, and it is easy to cause plaque dislodgement in the blood vessel, leading to new cerebral infarction and further aggravation of the condition. 2. Cerebral hemorrhage: endovascular damage and rupture of blood vessels can occur during the operation, leading to cerebral hemorrhage. 3. Thrombosis or embolism in other parts of the body: postoperative hypercoagulable state, the patient is bedridden, there may be venous thrombosis in the lower limbs, and embolus dislodgement may lead to pulmonary embolism. It is directly life-threatening. Before doing brain stent surgery, it is recommended to get a detailed understanding of the contents related to the surgery from a professional doctor and consult the specific precautions.