The cause of chest tightness when lying down and standing up may be cardiogenic chest tightness, such as cardiac insufficiency, myocardial ischemia, etc. It may also be caused by pulmonary chest tightness, such as chronic obstructive pulmonary disease and pleural effusion. 1. Chest tightness of cardiac origin: including cardiac insufficiency and myocardial ischemia. When the patient lies down, the blood return of the heart increases, resulting in increased burden on the heart, cardiac insufficiency, myocardial ischemia patients may have paroxysmal dyspnea at night, which can be relieved by standing. 2. Chest tightness of pulmonary origin: such as chronic obstructive pulmonary disease, pleural effusion. The patient is self-conscious of chest tightness and shortness of breath, subjective feeling of insufficient air, poor breathing, chest tightness when lying down. If the patient appears to lie down on the chest tightness standing on the situation, it is recommended to go to the hospital in a timely manner to find out the cause of the disease, and actively cooperate with the doctor’s treatment.