When sudden chest pain occurs, people first think that there is something wrong with the heart. In fact, there are many diseases that can cause chest pain, which need to be diagnosed at the hospital and then choose the right treatment. Coronary heart disease angina pectoris. It is the most common cause of chest pain and mostly occurs after exertion, full meal and emotional excitement. It usually manifests as pressure pain, stuffy pain and hidden pain in the left chest. It often spreads to the back, the inner side of the left arm, teeth, etc. The duration varies, and usually does not exceed 30 minutes. If the attack is relieved by rest or oral nitroglycerin, the diagnosis is basically made. If the pain worsens, lasts more than half an hour, sweats profusely during pain, is accompanied by nausea, vomiting, etc., and oral nitroglycerin is not effective, we should be alert to the possibility of acute heart attack. Be sure to seek medical attention without delay. Pneumothorax. Some young people suddenly have chest pain when carrying heavy objects, and X-ray examination reveals that it is a “pneumothorax”, and this kind of spontaneous pneumothorax is mostly seen in young adults. The typical manifestation is sudden onset of chest pain, accompanied by chest tightness, breath-holding, coughing, and sometimes shortness of breath, choking, irritability, cyanosis, sweating, shock, etc. Pleurisy. If the chest pain is aggravated by deep breathing or coughing, it indicates that there is inflammation of the pleura, mostly in patients with tuberculosis or lung tumors. Patients with pleuritic pain will press their hand against one side of the chest wall to avoid deep breathing, or to suppress coughing. After a period of time, the chest pain may move from one location to another. In addition, if a lung tumor spreads to the chest wall or ribs, it can cause persistent, intractable chest pain, which can usually be confirmed by a chest radiograph or chest CT. Digestive fluid reflux. Chest pain can also be caused by problems in the digestive tract. If gastric and duodenal secretions reflux into the esophagus, it can cause chest pain with heartburn and acidity. The chest pain may radiate to the shoulder and inner upper arm, much like angina-like chest pain, and requires an electrocardiogram and other tests to identify it. Thoracic disc herniation. It occurs mostly after strenuous activities, and the examination of the heart, lungs and digestive tract are fine, but the patient often has severe pain, which is caused by the herniated thoracic disc compressing the thoracic nerve. Because it is relatively rare, it is often misdiagnosed clinically as angina pectoris, and some patients have had heart stents put in as a result, but the pain remains unabated. Generally speaking, the diagnosis can be confirmed by MRI of the thoracic spine, and minimally invasive surgery is effective.