Symptoms of myocardial ischemic angina can include chest tightness and chest pain in the precordial region or behind the sternum, discomfort in the back of the shoulder and left upper arm, tightness in the throat, toothache, etc. and the symptoms usually last for less than 15 minutes and can be relieved after rest or taking medication. If the symptoms are not relieved for more than 30 minutes, be alert to the possibility of acute myocardial infarction. It is recommended to have nitrate drugs around, commonly used are nitroglycerin, isosorbide nitrate, etc. At the onset of symptoms, it is recommended that an electrocardiogram be done as soon as possible, and coronary CT or coronary angiography should be improved to understand the degree of coronary artery stenosis in the heart to guide further treatment.