Cardiovascular function is most sensitive to changes in temperature, and sudden increases or decreases in temperature can trigger angina pectoris or even myocardial infarction. Although autumn has arrived, temperatures are still unrelenting, and all patients with underlying heart disease should still pay more attention to heart heat protection. High temperatures bring challenges to patients with underlying cardiovascular disease High temperatures make the subcutaneous blood vessels dilate, skin blood flow increases 3-5 times more than usual, blood flow back to the heart also increases significantly, sympathetic excitability increases, heart rate accelerates, all of which can increase the burden on the heart and induce underlying heart disease. Higher temperatures lead to more sweating and higher blood viscosity, which can induce ischemia or cardiovascular blockage, and in serious cases can cause myocardial infarction; hot and dry weather may lead to lower sleep quality, and poor rest is one of the important triggers of heart attack, which can easily induce acute attacks of cardiac insufficiency or myocardial ischemia; summer air is wet and heavy, with low air pressure and lower oxygen content, which can easily lead to hypoxia. Patients with heart valve disease and coronary heart disease often feel chest tightness and shortness of breath even when there is no difference between activity and usual, and acute myocardial infarction and cardiac insufficiency can occur in severe cases. Hot weather, air conditioning indispensable, air conditioning filter cleaning is not timely, will be easy to accumulate dust, the incidence of respiratory infections subsequently increased, is an important cause of wind heart disease, cardiac insufficiency; hot weather will make cardiovascular disease patients sympathetic excitement, coupled with poor body heat distribution, especially prone to the onset of cardiac neurosis. How to do a good job of heart heat protection: heat protection and cooling Outdoor exercise is best to choose a cooler early morning or evening, do not exercise in the hot sun. And, the intensity of the activity should be appropriate, and the activity time should not be too long; when the air humidity is high, outdoor activities should be reduced, more rest at home. When going out, avoid direct sunlight, wear shading equipment and have enough cited water. Do not set the temperature too low when cooling the air conditioner indoors. Pay attention to work and rest rules: The heat is still prevalent, the day is long and the night is short, you may sleep late at night, pay attention to ensure sufficient sleep time, and take a proper rest at noon. The hot weather, reduced appetite, reduced digestive function, patients with underlying cardiovascular disease we would have advocated a low-salt, low-fat, light diet. The national diet is characterized by the fact that dinner is probably the most abundant during the day, and we need to pay attention to the fact that dinner should not be too full. Eating more green leafy vegetables and vegetables and fruits that contain more carotenoids can help reduce atherosclerosis. Eat pork and lamb with high fat content, but choose fish and shrimp or muscle with higher protein content and lower fat content, and eat less greasy food such as too much barbecue and frying. On time hydration: summer sweating, drink more water, timely hydration, do not wait for thirst to drink water. It is best to drink cold water, you can also drink some light salt water, summer can be appropriate to quote green tea. Drink less caffeinated beverages, and do not drink a lot of frozen drinks at once, cold stimulation will induce coronary vasoconstriction, inducing angina. Chrysanthemum tea, green bean soup and other traditional drinks to avoid the summer heat can also be chosen, but pay attention to the seasoning use of sugar in moderation!