Non-culprit Vessels for ST-Segment Elevation Myocardial Infarction

Inclusion Criteria: * age 18 to 75 with continuous ischemic chest pain for ≥ 30 minutes and ST-segment of electrocardiographic leads between V2 and V3 elevated ≥ 0.2 mV (or ≥ 0.1 mV in ≥ 2 other continuous electrocardiographic leads), cardiac troponin I (cTn I) elevation of \> 0.05 ng/ml, coronary arteriography within 12 hours after the onset of symptoms indicating lesion in culprit vessel with thrombolysis in myocardial infarction (TIMI) flow grade 0 to 1, merely underwent PPCI. Additionally, coronary arteriography corroborates lesions in non-culprit vessel (Besides the culprit vessel, there are ≥ 70% stenoses in one or more coronary vessels in which diameters were ≥ 2 mm). Exclusion Criteria: * left main coronary artery disease, cardiogenic shock, complete left bundle branch block (CLBBB) PPCI treated culprit and non-culprit vessels, PPCI failure patients with postsurgical haemodynamic instability or spontaneous ischemia, ≥ 70% stenoses of vessels remained during the hospitalization after staged PCI, history of PCI or Coronary Artery Bypass Grafting (CABG), history of chronic cardiac failure, bleeding diathesis, prior administration of thrombolytic therapy, known thrombopenia or leucopenia, sever liver and kidney dysfunction, active infection, immune system and connective tissue diseases, known contraindications to aspirin or heparin, life expectancy \< 1 year, had major procedure within 3 months, uncontrolled hypertension, ischemic stroke within 30 days, hemorrhagic stroke, intracranial diseases including and arteriovenous malformation, extensive traumatic cerebral infarction within 6 weeks, oral anticoagulant therapy, severe myocardial infarction related complications and perioperative death