Typical acute coronary syndrome presents with episodes of retrosternal dullness, tight crushing or pressure, burning sensation, which may radiate to the left upper arm, jaw, neck, back, shoulder or ulnar side of the left forearm, intermittently or continuously, accompanied by sweating, nausea, dyspnea, choking sensation, or even syncope, lasting >10 to 20 minutes. Some patients have prodromal symptoms such as weakness, chest discomfort, palpitations on activity, shortness of breath, irritability, and angina pectoris for several days prior to the onset of AMI. Atypical manifestations include toothache, sore throat, vague epigastric pain, dyspepsia, pins and needles pain in the chest or only dyspnea. Acute coronary syndrome is a common critical illness in cardiology. Foreign studies have shown that regardless of the clinical manifestations of acute coronary syndrome, the 1-year mortality rate is high, about 15%, and the 5-year cumulative mortality rate is even as high as 20%.