Carotid artery stenosis, nowadays, has become a common cerebrovascular disease that threatens human life and health. The carotid artery is a large blood vessel that carries blood from the heart to the head, face and neck, and is one of the main blood supply vessels to the brain. It is reported that more than 60% of cerebral infarction is caused by blockage of the carotid artery, and cerebral infarction can be disabling or even fatal if it is very serious. This shows how serious the consequences of carotid artery blockage are, and some patients ask what to do about left carotid artery blockage. In fact, regardless of whether the left carotid artery is blocked or the right carotid artery is blocked, the reason is actually the same. Carotid artery blockage is usually caused by hypertension, diabetes, hyperlipidemia and other causes of atherosclerosis. Atherosclerosis will cause carotid artery intima to proliferate, deform, ulcerate, calcify and even form plaque, resulting in carotid artery blockage. After the blockage of carotid artery, there will be insufficient blood supply to the brain and cerebral ischemia, which is very dangerous, so once the diagnosis of carotid artery blockage is confirmed, timely treatment is necessary. The most thorough and effective treatment for carotid artery blockage is carotid endarterectomy, which is performed under a microscope to peel off the diseased carotid artery intima and restore the smooth inner wall and normal internal diameter of the carotid artery, and is the first surgical treatment for patients with carotid artery stenosis.