Myocardial infarction can be caused by a variety of factors, such as coronary artery atherosclerosis, increased myocardial oxygen consumption, insufficient oxygen supply, embolism and so on. 1. Coronary artery atherosclerosis: due to lipid deposition in the blood vessel wall, the lumen of the blood vessel can be narrowed, and in severe cases, it can be completely occluded, resulting in insufficient blood supply to the local myocardium and triggering myocardial infarction. 2. Increased myocardial oxygen consumption: it can be caused by high blood pressure, tachycardia and other diseases, due to increased oxygen consumption leading to myocardial hypoxia, which may cause myocardial infarction in severe cases. 3. Insufficient oxygen supply: it can be caused by chronic heart disease, anemia and other diseases, when the long-term insufficient oxygen supply can make myocardial cell degeneration and necrosis, and cause myocardial infarction. 4. Embolism: Coronary artery embolism is triggered by the dislodged embolus of deep vein thrombus, at this time, the blood supply of the local myocardium drops sharply, and the long-term insufficient blood supply to the myocardium can lead to myocardial infarction. Myocardial infarction should be timely medical treatment, under the guidance of the doctor to identify the cause of the disease and carry out the appropriate treatment, not blind judgment, so as not to delay the condition.