It is found that nearly 50% of AMI cases have predisposing factors
1. Emotional excitement
Myocardial infarction is closely related to emotional changes such as excitement, tension and anger. In the case of emotional excitement, blood pressure can be increased, catecholamine secretion increased, resulting in a significant increase in left ventricular load, myocardial oxygen demand, aggravating coronary artery insufficiency, thus inducing myocardial infarction. We often see some people in the film and television programs because of emotional over excited sudden myocardial infarction and hands tightly over the chest, and in reality also often encounter in playing cards or watching football games, because of the mood is too nervous to induce acute myocardial infarction.
Constipation is a common disease in middle-aged and old people, but its harmfulness has not been paid enough attention to. Clinically, it is not uncommon to have myocardial infarction due to forced breath holding due to defecation. Therefore, the elderly with coronary heart disease should pay attention to develop the habit of regular defecation, if necessary, can take some measures to moisten the intestines.
3. Physical and mental overwork
Excessive physical labor and long-term mental work may aggravate the burden on the heart and increase the myocardial oxygen demand suddenly. If the patient's own coronary artery has sclerosis, stenosis, can not fully expand, it is easy to cause myocardial ischemia. Ischemia and hypoxia can cause arterial vasospasm, which in turn aggravates myocardial hypoxia, and can lead to myocardial infarction in severe cases.
The risk of acute myocardial infarction can be induced by eating a lot of food, drinking a lot of alcohol and eating a lot of fatty substances, especially in elderly patients. After eating high calorie and high-fat meal, blood lipid concentration will rise suddenly, blood viscosity will increase, platelet aggregation will increase, and local blood flow will be slow, which will promote thrombosis and lead to acute myocardial infarction. The incidence rate of acute myocardial infarction is high in foreign countries, which is related to overeating.
Cold stimulation, especially walking in front of cold wind, can easily cause sympathetic excitation. On the one hand, it can increase blood pressure, heart rate, systolic blood vessels of systemic circulation, increase peripheral resistance, and increase myocardial oxygen consumption; on the other hand, it can cause vasoconstriction and reduce myocardial blood supply, both of which promote myocardial ischemia, and serious and lasting ischemia can cause myocardial necrosis. Therefore, winter must pay attention to cold and warm.
Hypotension caused by anesthesia during operation and neuroendocrine imbalance under severe emergency state are also the causes of myocardial infarction, especially for the elderly. In addition, massive hemorrhage, shock, severe arrhythmia, etc., may trigger atherosclerotic plaque rupture, thrombosis and lead to sustained myocardial ischemia and myocardial infarction.