Myocardial ischemia is usually caused by coronary artery spasm or coronary artery stenosis. Coronary artery spasm usually has no organic disease, and some patients may experience myocardial ischemia caused by coronary artery spasm after exertion, mood swings or cold, which can be relieved after removing the triggering factors. Coronary artery stenosis causing T-wave hypoplasia or inversion is usually pathological and requires coronary angiography to clarify the degree of stenosis and which vessel is stenosed. If the stenosis is mild, it can be treated conservatively with internal medicine. If the stenosis is severe, stenting is required. In the case of multiple stenoses, cardiac bypass surgery should be considered to improve the blood supply to the heart. Myocardial ischemia is usually caused by coronary artery disease, which is an atherosclerotic heart disease, and the gold standard for coronary artery disease diagnosis is coronary angiography. The gold standard for coronary artery disease is coronary angiography. In normal times, it is necessary to take regular oral medications for coronary artery dilation, adjust blood lipids, stabilize atherosclerotic plaques and antiplatelet aggregation and other treatment principles.