Abstract: Objective To explore the relationship between ST-segment level,T-wave early inversion and patients' left ventricular function,prognosis specifically for ST-segment elevation acute myocardial infarction patients,which underwent emergency PCI.Methods 62 patients (M:40,F:22 ) with acute myocardial infarction were randomly divided into groups as follows:according to whether one hour ST segment's changes more than 50% after PCI,they were divided into group A and B:group A (PCI after one hour ST segment ≥50% ),group B (PCI ST segment after one hour <50% ).According to whether 24-hour T wave inversion after PCI,they were divided into group C and D:group C (24-hour T-wave inversion),group D (24 hours without T wave inversion).After six months,the different LVEF betweeen group A and B,C and D was observed.Results Of group A and group C,after 6 months,the left ventricular function recovery was better than that of group B and group D ( P < 0.05 ).Conclusion The analysis of ST segment and T wave are simple,practical and effective methods to predict myocardial reperfusion,especially for PCI therapy in patients with acute myocardial infarction.