There are three main possibilities for chest pain in the morning: 1, physiological factors, when sleeping at night in the habitual lateral or prone position, due to the pressure on the chest muscles resulting in the accumulation of local metabolites, the chest can be sore and painful discomfort after waking up in the morning; 2, cardiovascular system diseases, such as coronary heart disease, due to vagal nerve excitation at night, there can be no obvious clinical manifestations, due to the morning skin temperature temperature difference, when cold or Due to the large difference in skin temperature in the morning, when cold or heat can cause sympathetic excitation, resulting in coronary artery constriction, myocardial ischemia, manifested as pain and discomfort in the anterior thoracic region, and can be radiated to the back, sublingual nitroglycerin can be relieved; 3, reflux esophagitis, due to the change in position in the morning, can lead to a sudden decrease in the content of gastric acid in the esophagus, stimulating the mucosa of the esophagus to appear behind the sternum burning pain, and can be accompanied by acid reflux and belching discomfort.