Chest tightness dyspnea chest pressure may be caused by respiratory diseases, cardiovascular diseases and so on. 1. Respiratory system diseases: emphysema, pneumonia, etc. all lead to this symptom. (1) Emphysema: Emphysema affects the gas exchange function of the lungs, making the body lack of oxygen, which easily induces the above symptoms. (2) Acute bronchitis: Acute bronchitis will cause irritation to the bronchial tubes, so that oxygen cannot enter the body normally, which may also cause the above symptoms. (2) Cardiovascular disease: patients with coronary heart disease may suffer from myocardial ischemia. After lying down, it is easy for the blood in the body to be unable to be sent to many organs in the body, and it is easy for the lack of oxygen to occur, leading to the existence of the above symptoms. The cause of chest tightness and breathlessness and pressure in the chest is more complex, and patients should receive timely treatment to prevent the worsening of the above symptoms.