Chest and undershirt pain at the same time may be due to angina pectoris, myocardial infarction, reflux esophagitis and other diseases. 1. Angina pectoris: angina pectoris mainly occurs after emotional excitement or strong high-intensity activities, usually the symptoms are episodes of anterior heart area, the back of the sternum, the back of the pain like pins and needles, and there may also be a pressure-like pain. Some patients are also accompanied by panic, chest tightness and other symptoms. 2. Myocardial infarction: Myocardial infarction is one of the more common acute and severe diseases in cardiovascular medicine, which will lead to severe and persistent pain in the whole chest or anterior heart region, and when the symptoms are severe, it will radiate to the back and back pain will occur. 3. Reflux esophagitis: Reflux esophagitis can lead to heartburn, acid reflux, bloating, hiccups and other symptoms, some patients will irritate the esophagus during the attack of reflux esophagitis, which will cause chest pain symptoms, and when the pain is severe, it will radiate to the back and back pain will occur. When patients experience pain in the chest and undershirt at the same time, it is important to pay attention to timely medical examination.