Usually increased sympathetic nerve activity, full meal, strenuous exercise, trauma may induce myocardial infarction. 1. Increased sympathetic nerve activity: usually at 6-12 o’clock in the morning after waking up, there will be an increase in sympathetic nerve activity, which makes the body’s stress reactivity, myocardial contractility, heart rate and blood pressure increase, leading to an increase in the tension of coronary arteries, which will induce myocardial infarction. 2. Satiety: after a full meal, especially after eating a large amount of food, blood will flow into the gastrointestinal tract, the relative supply of blood to the heart is insufficient, which may induce myocardial infarction. 3. Strenuous exercise: after heavy physical activity, emotional over-excitement, it will lead to a significant increase in the load on the left ventricle, which may also cause induced myocardial infarction. 4. Other conditions: shock, trauma, severe arrhythmia and other factors, will lead to a sudden drop in cardiac blood flow, so that the coronary artery perfusion is reduced, may also induce myocardial infarction. When myocardial infarction occurs, it is recommended to consult a doctor in time, under the guidance of the doctor for treatment.