Cardiac ischemia can manifest as chest pain, chest tightness, dizziness and nausea. Typical symptoms of insufficient blood supply to the heart are chest pain or chest tightness, mostly seen in patients with coronary angina pectoris. Angina pectoris attack will be manifested as a dull pain in the precordial region, pain can be radiated to the left upper limb or jaw, the pain time is mostly 3~5 minutes, rarely more than 20 minutes, after rest or take medication can be relieved. Myocardial infarction is more serious, patients often have severe pain in the precordial area, accompanied by sweating and a sense of dying, taking nitroglycerin and other drugs can not be relieved. Some patients may experience dizziness during myocardial ischemic attack, which may be related to the increase in blood pressure during myocardial ischemic attack, and a few patients may experience a drop in blood pressure, resulting in insufficient blood supply to the brain. Myocardial ischemia can also reflexively cause nausea, especially the lower wall myocardial ischemia, nausea is more likely to occur. The symptoms of myocardial ischemia are varied, and middle-aged and elderly patients with related symptoms should go to the hospital in a timely manner and be treated under the guidance of a physician to avoid delays in their condition.