Heat will have an impact on coronary heart disease, in the summer, hot summer is not recommended for coronary heart disease patients to stay outdoors for a long time, because in the hot environment patients sweat more, if not timely replenishment of water, blood vessels and in a dilated state, it is easy to lead to low blood pressure, accelerated heart rate, coronary artery vascular perfusion is insufficient or due to mood swings, blood pressure will suddenly rise again. Blood pressure, heart rate instability can lead to increased myocardial oxygen consumption in patients with coronary heart disease, myocardial ischemia easily, angina attack, serious cases will occur myocardial infarction and endanger the lives of patients. It is recommended that patients with coronary artery disease should go out as little as possible on hot days and rehydrate in a timely manner, take medication on time as prescribed by the doctor, and follow up regularly to reduce the occurrence of myocardial ischemia and improve the prognosis of patients with coronary artery disease.