Young people with chest tightness and breathlessness are classified into functional and organic according to the pattern and severity of attacks. Organic diseases are mainly related to impaired cardiopulmonary function, and acute attacks of severe chest tightness require immediate medical attention to rule out the possibility of life-threatening causes. Young people with chest tightness and breathlessness may be related to the following causes: cardiac causes: more common is coronary heart disease. If a young person has been physically fit in the past and suddenly develops unexplained chest tightness and breathlessness, it may be related to the occurrence of acute myocardial infarction. Although the prevalence of coronary heart disease is more than 40 years of age, but in recent years the onset of the trend is younger, can not be ignored. Another relatively common cause is viral myocarditis, which causes impaired cardiac function due to viral invasion of the heart muscle. Cardiac enzymes, troponin, electrocardiogram, echocardiogram, coronary CT, cardiac MRI or coronary angiography can be used to clearly rule out heart disease problems. Pulmonary causes: more common pulmonary infections, spontaneous pneumothorax, lung cancer, etc. Lung infections such as lobar pneumonia can lead to solid lung changes; in spontaneous pneumothorax, the lung will be squeezed and shrunk due to the disappearance of negative chest pressure; bronchial compression or pleural effusion caused by lung tumors can cause impaired air exchange function to the lung. Therefore, it is also necessary to rule out lung problems when young people have chest tightness and breathlessness. Chest X-ray, lung CT, bronchoscopy and other tests can be used to clearly investigate whether there is a lung infection or tumor. If no organic lesion is found after cardiopulmonary function tests, functional diseases such as cardiac neurosis or psychological causes should be considered, and further treatment can be provided at a psychosomatic medicine clinic.