Shortness of breath in the chest is clinically referred to as shortness of breath. There are many reasons for shortness of breath. The common clinical ones include the following categories: The first category is cardiovascular system diseases, such as coronary atherosclerotic heart disease, myocardial ischemia, which is often referred to as coronary heart disease. Such patients usually have chest pain, chest tightness, and wheezing after activity, and the symptoms can be relieved after resting for a while or applying coronary artery-dilating drugs. In addition heart failure can also cause chest tightness and breathlessness. The mechanism of heart failure is that the heart, for various reasons, has a reduced pumping capacity and cannot pump blood effectively into the blood vessels, causing blood to accumulate in the heart and blood vessels, which results in chest tightness and shortness of breath. This type of patient is usually worse at night after lying down. Application of cardiotonic drugs can provide some relief. The second category is respiratory system diseases, trachea, lung lesions, due to airway spasm or obstruction, such as chronic obstructive pulmonary disease, asthma, etc., or for various reasons, the alveoli capable of gas exchange reduced, such as pneumonia, pulmonary atelectasis, lung occupational lesions, etc., can cause chest tightness, breathlessness. The third category is due to psychological factors, patients with anxiety, tension, poor sleep can also cause chest tightness and breathlessness. If the patient has the symptoms of chest tightness and breathlessness for a long time, it is recommended that the patient should go to the hospital in time to perform relevant examinations to clarify the diagnosis and treatment so as not to delay the condition.