If the middle of the night chest tightness, shortness of breath, dyspnea, the most common are two situations: 1, heart failure, such as left heart failure, patients appear at night paroxysmal sleep dyspnea, often accompanied by sweating, panic, these patients are often accompanied by organic heart disease, usually with exertional dyspnea, often accompanied by multiple high-risk factors for heart disease without respiratory disease, often accompanied by decreased urinary output, swelling of the lower limbs, etc., it is better to go to the hospital 2, pulmonary dyspnea, clinical common asthma, chronic obstructive pulmonary disease acute exacerbation, and acute exacerbation of chronic bronchitis, etc., these patients often have a history of lung disease, often have a history of smoking, dyspnea and body position does not have a clear relationship between the BNP is not high in the blood test, but also need to go to the hospital for further clarification, to guide the further diagnosis and treatment.