Chest pain is one of the most common clinical symptoms, and some data show that patients with acute chest pain as the main complaint account for 5% to 20% of emergency medicine patients. The clinical manifestations of acute chest pain vary widely, and the risk also varies greatly. For life-threatening and dangerous diseases, such as acute coronary syndrome, aortic coarctation, pulmonary embolism and tension pneumothorax, proper diagnosis and management are required within a short period of time, and misdiagnosis or omission can lead to serious or even fatal consequences. First, let’s talk about the chest pain diseases that may be life-threatening: acute coronary syndrome: it is caused by narrowing or occlusion of the coronary arteries of the heart, and its symptoms are a crushing, boring pain behind the sternum with a feeling of tightness, and the pain radiates to the back of the shoulder, the left upper arm, the lower jaw throat or the upper abdomen, and lasts for several minutes, mostly. It can be relieved by sublingual nitroglycerin. Elderly, female, and diabetic patients may have atypical symptoms and may have only dull discomfort in the precordial region and posterior back. In contrast, acute myocardial infarction pain lasts more than 30min and up to several hours, with the risk of malignant arrhythmia, cardiogenic shock, and heart rupture. These diseases must be treated as soon as possible in a hospital. Acute aortic coarctation: The disease has an acute onset, and patients often have a history of hypertension. The disease occurs with a sudden onset of severe burning or tearing pain in the precordial region or behind the sternum, which can reach its peak within a few seconds. It can radiate to the head, neck, upper extremities, back, lumbar, middle and lower abdomen and even lower extremities, lasting from several hours to several days, and is not relieved by nitroglycerin. There is no dynamic evolution of the electrocardiogram, and a widened aortic shadow is seen on X-ray, and aortic strengthening CT can make a clear diagnosis. Acute pulmonary artery embolism: The disease can occur suddenly with chest pain, dyspnea, cyanosis, and even shock symptoms, occasionally with fever, cough, and hemoptysis. Pleural friction sounds and wet rales may be present. Most often there is a history of trauma, bed rest, and recent surgery. Arterial blood gases show hypoxemia and hypocapnia with increased D-Dimer. Enhanced CT may confirm the diagnosis. Spontaneous pneumothorax: The patient feels sudden chest pain and dyspnea, and the chest pain worsens with deep breathing. Tension pneumothorax may have clinical manifestations of circulatory collapse or even coma. On examination, the affected side of the chest is full, the trachea is displaced to the healthy side, and the breath sounds are diminished or disappeared. x-ray shows increased translucency on the affected side, no lung texture is visible, and the lung is compressed. The chest wall tissue structure and organs and tissues in the chest cavity as well as the diaphragm and some organs under the diaphragm can cause chest pain under the action of inflammation, ischemia, trauma, tumor, mechanical compression, and physical and chemical stimulation. Chest pain related to heart disease (non-acute coronary syndrome): for example, pericarditis, regardless of the cause of fibrinous pericarditis can cause chest pain, especially the chest pain of non-specific pericarditis is the most intense. This kind of chest pain tends to be more intense and has a clear relationship with breathing, which may be severe with deep inspiration and can be aggravated or alleviated by changing position. Another kind of hypertrophic cardiomyopathy is the main symptom of exertional chest pain with dyspnea, palpitations and syncope, this can be diagnosed by doing echocardiography. Chest pain caused by non-cardiac structures: for example, lesions of lung tissue, trachea, bronchus and blood vessels of the lung can cause chest pain, such as lobar pneumonia, lung cancer and severe pulmonary hypertension. These need to be clarified by perfecting lung CT, etc. Acute pleurisy, pleural mesothelioma and lung cancer involving the pleura can all cause chest pain, which lasts longer and is different in nature from chest pain of heart disease. Some patients also have esophageal cardia achalasia, reflux esophagitis, and mucosal tearing of the lower esophagus (Mallory-Weiss syndrome), and the symptoms of these diseases are sometimes easily confused with angina pectoris. Diseases of chest wall tissues: skin, muscles, rib cage rib cartilage, and intercostal nerves distributed in the thorax can cause chest pain when there is inflammation, injury or infection, such as costochondritis, herpes zoster, etc. For patients with chest pain with localized pressure pain in the chest wall should first consider diseases of the chest wall tissues. Diseases of abdominal organs can also cause chest pain symptoms: for example, stomach, duodenum, pancreas, liver, gallbladder, etc. Most of the lesions of these organs manifest as abdominal pain or thoracoabdominal pain, and in rare cases, they can manifest as chest pain only, which can easily lead to misdiagnosis at this time. The last type is functional chest pain: among the chest pain in young people and menopausal women, functional chest pain occupies a considerable proportion, and the common ones are cardiac neurosis and hyperventilation syndrome. Chest pain is one of the most common clinical symptoms, and more and more hospitals have set up “chest pain centers”. If you have chest pain and other symptoms, you should consult a doctor at the first time, and a professional doctor will determine whether the chest pain is serious and life-threatening according to the nature of your pain and auxiliary examinations, and further give active treatment.