The causes of vague pain under the heart are many and may include heart disease, gastroesophageal reflux disease, peptic ulcers, and hepatobiliary disease. The lower part of the heart is close to the upper abdomen, where the organs include the heart, lower esophagus, stomach, gallbladder and left lobe of the liver, so disorders of these organs may cause painful sensations. The diseases that may be associated with vague pain under the heart are as follows: 1. Cardiovascular system diseases: The first symptom of vague pain under the heart needs to exclude coronary heart disease. Coronary heart disease (angina pectoris, heart attack, etc.) can cause myocardial ischemia and hypoxia, and the clinical manifestations include chest tightness and chest pain. The typical site of chest pain is behind the sternum, but atypical cases can also be manifested as vague pain under the heart. The pain of angina pectoris is mostly related to exertion, emotional excitement and full meals, and can be relieved by rest or nitroglycerin inhalation. Further differential diagnosis of heart disease problems can be made through auxiliary examinations. 2, digestive system diseases: symptoms of gastroesophageal reflux disease, peptic ulcer and biliary tract diseases may be manifested as vague pain under the heart, which can be initially identified according to different accompanying symptoms. Gastroesophageal reflux disease is caused by the reflux of gastroduodenal contents into the esophagus causing discomfort. It is often accompanied by acid reflux and heartburn, and is aggravated by lying down or by increased abdominal pressure. Peptic ulcers often occur in the stomach and duodenum, and patients generally complain of epigastric pain. However, digestive disorders are not significantly related to exertion, but are influenced by feeding and antacid therapy, etc. Left lobe lesions of the liver or gallbladder lesions also cause vague epigastric pain. It can be clarified by barium meal examination, gastrointestinal endoscopy or ultrasound. Since there are more organs below the heart, patients should not diagnose themselves with medication based on symptoms alone, and regular hospital consultation is recommended.