Cardiothoracic pain may be cardiac pain or pain caused by other tissues and organs in the chest. Possible causes include cardiovascular disease, respiratory disease, mediastinal disease, and other rare diseases. 1. Cardiovascular diseases: including coronary heart disease, acute pericarditis, hypertrophic cardiomyopathy, heart valve disease, thoracic aortic coarctation, and pulmonary embolism. 2. Respiratory diseases: including left-sided lobar pneumonia, left-sided lung cancer, left-sided pneumothorax or hemothorax, left-sided pleurisy or pleural tumor. 3. Mediastinal diseases: including mediastinitis, mediastinal tumor, mediastinal emphysema, esophageal hiatal hernia and so on. 4. Other diseases: it is relatively rare for these diseases to cause cardiothoracic pain, such as left subphrenic abscess, left lobe abscess, splenic infarction, esophagitis and so on. Cardiothoracic pain suggests that patients go to the hospital as soon as possible, especially acute myocardial infarction, thoracic aortic coarctation, pulmonary embolism, etc. is a clinical emergency, if the treatment is not timely may lead to the death of the patient, and if necessary, you need to call the emergency number for rescue.