Myocardial infarction, also known as myocardial infarction, refers to a sharp reduction or interruption of coronary blood supply on the basis of coronary artery lesions, causing severe and persistent acute ischemic necrosis of the corresponding myocardium. The clinical manifestations are sudden, severe and persistent pain behind the sternum, characteristic dynamic changes in electrocardiograms and increased serum enzymes. Complications such as arrhythmia, heart failure, and shock may occur, which can often be life-threatening. The symptoms of myocardial infarction in most people are chest pain and chest tightness. The causes are generally excessive fatigue, emotional excitement, overeating, shock after major surgery or massive hemorrhage, etc. In terms of age, middle-aged men between the ages of 45 and 60 are at high risk of myocardial infarction.