Whether myocardial ischemia is a serious disease or not is related to the location and degree of coronary artery stenosis and whether the plaque is stable. If the coronary artery is slightly narrowed, or only the distal branches are narrowed, it is generally not serious and is not considered a major disease. On the contrary, severe stenosis of the coronary artery, or lesions in the main stem or multiple branches of the blood vessels, which may cause sudden death, are very serious and should be regarded as major diseases. If the stenosis is in a small branch, it is usually not serious. If the stenosis is in the main trunk, it may easily lead to severe ischemia. A mild degree of stenosis, such as a 50% stenosis, is generally not serious; a stenosis of more than 75% may lead to severe ischemia. Stable vascular plaques are generally not serious; vascular plaques that rupture and become unstable are prone to thrombus aggregation, blocking blood vessels and causing severe ischemia. Myocardial ischemia should be treated in a regular consultation with a cardiologist under the formal guidance of a professional doctor.