There are individual differences in the clinical manifestations of myocardial ischemia. Typical symptoms are angina pectoris, which manifests as pain in the precordial region, chest tightness, palpitations, and so on. Once the above symptoms appear, rest immediately, can contain nitroglycerin to relieve the symptoms, if the symptoms continue to be unable to relieve, to seek immediate medical attention, but need to pay attention to not drive or walk to the hospital, should call 120.