A hot day with a hard heart is prone to heart discomfort under hypoxia and ischemia if one has a heart disease or a low tolerance to heart hypoxia, resulting in an increased heart rate. Heart trouble in hot weather is a very common phenomenon, formed by many reasons, such as lack of yang in the body, lack of oxygen, lack of air circulation and lung diseases. When the weather is hot in summer, people’s qi and blood are emitted outside, resulting in a lack of yang in the body, which can easily lead to symptoms such as chest tightness, shortness of breath and excessive sweating. In the case of middle-aged and elderly people who have difficulty with their hearts in the heat, especially if they usually have high blood pressure and diabetes, coronary heart disease should be further ruled out. Usually there is no underlying disease, because of the hot days appear heart difficulty, to pay attention to the heat prevention and cooling.