In recent years, chest pain has been clinically emphasized as a common symptom of GERD. Its pain site is usually in the posterior sternum, subxiphoid or upper abdomen, often radiating to the chest, back, shoulder and neck, jaw, ear and upper limbs, with more radiation to the left arm. A few patients have numbness in the hands and upper limbs. Gastroesophageal reflux disease and several esophageal dysmotility disorders (such as diffuse esophageal spasm, nutcracker esophagus, lower esophageal sphincter hypertension, etc.) can cause chest pain, which is collectively called “esophageal-derived chest pain”. The characteristics of esophageal chest pain include: pain lasting more than one hour, mostly after meals, pain without radiation, and may be accompanied by esophageal symptoms such as heartburn, acidity, and dysphagia, which can be relieved by antacids. The response to nitroglycerin does not identify the pain as cardiogenic or noncardiogenic, and some studies have found that patients with cardiogenic and noncardiogenic chest pain have similar responses to nitroglycerin. Since the projection of sensory nerve fibers on the body wall and skin of esophagus and heart overlap each other, C8~C10 for esophagus and T1~T4 for heart, so the esophageal chest pain is similar to the angina pectoris attack of ischemic heart disease, and it is difficult to distinguish the two from each other in terms of localization. Moreover, the pain symptoms of both are aggravated after a full meal and can be relieved by nitroglycerin, so it is even more difficult to distinguish them. Some experts performed 24-hour esophageal Ph monitoring on 50 patients who complained of severe “angina pectoris” but had normal cardiac function tests and coronary angiography results, and found that 46% of the patients had gastroesophageal reflux, which may be the cause of pneumothorax pain. At Peking Union Medical College Hospital, endoscopy and esophageal function tests were performed on 52 patients with angina-like chest pain from cardiac specialists, and 82.7% of cases were found to be caused by gastroesophageal reflux disease. In severe cases, the chest pain of GERD can be intensely irritating and radiates to the back, chest or even behind the ear. If a patient presents with persistent retrosternal pain or even radiates to the neck, it suggests a penetrating border ulcer or concomitant perioesophagitis. Of course, there is no constant relationship between the degree of chest pain (retrosternal or epigastric pain) and the severity of esophagitis, and endoscopy in patients with painful symptoms does not necessarily reveal acute inflammation of the esophagus; in short, patients with endoscopic esophagitis do not necessarily produce painful symptoms during acid perfusion. Back pain located between the two scapulae is most often seen in patients with severe chronic esophagitis and may be due to mediastinal irritation from peresophagitis. The mechanism of chest pain caused by GERD remains unclear and is considered to be related to several factors, such as the ionic concentration of acid reflux, the amount and duration of reflux, and secondary esophageal spasm. Patients with coronary artery disease often have combined esophageal disease, and some investigators have suggested that GERD can cause myocardial ischemia, but this view is still highly controversial. In recent years, it has been found that patients with non-cardiogenic chest pain have an esophageal hypersensitivity state, and their sensitivity to mechanical dilation, chemical stimulation and temperature stimulation is higher than that of normal volunteers, and the visceral hypersensitivity type may be one of the important mechanisms of non-cardiogenic chest pain caused by GERD. Moreover, the test results showed that the esophageal mucosa showed central sensitization after exposure to hydrochloric acid, further confirming that visceral hypersensitivity may be one of the causes.