Objectives To compare the different effects of late successful reperfusion with PCI on left ventricular function and its relationship with viable myocardium after acute anterior wall myocardial infarction in patients with or without diabetes. Methods A total of 125 consecutive subjects with acute anterior wall myocardial infarction were selected,and divided into diabetes mellitus(DM) group(n=43) and Non-DM group(n=82) according to WHO diabetes diagnosis criteria.All patients received successful PCI at 12±8 days from onset.Ischemic viable myocardium was detected with low-dose dobutamine echocardiography,and left ventricular function and wall motion abnormality were also assessed with echocardiography before PCI.The data of clinical manifestations and angiograms before and after PCI were analyzed. Levels of creatinine kinase-MB(CK-MB),and troponin T(TnT) before PCI,6 hours and 24 hours after PCI were assessed.All patients received clinic and echocardiography follow-up for 6 months.Results Higher rate of TIMI 2 flow,and lower rate of TIMI 3 flow in DM group were demonstrated immediately after PCI,and the rate of serum CK-MB and/or TnT levels were higher in DM group,compared with Non-DM group(P<0.05).63%of DM patients and 56%of non-DM patients had viable myocardium before PCI(P>0.05).There were no significant differences of left ventricular ejection fraction(LVEF),left ventricular end diastolic volume index(LVEDVI),left ventricular end systolic volume index(LVESVI),and wall motion score(WMS) between two groups at baseline before PCI(P>0.05).After six months,WMS was decreased and LVEF was increased in Non-DM group,but the WMS and the LVEF did not changed,and the LVEDVI was increased in DM group compared with baseline;the LVEDVI,LVESVI, LVEF,and WMS were significantly different between two groups(P<0.05 or P<0.01 ).Conclusions Compared with non-diabetics,delayed successful revascularization with PCI in diabetics patient with acute myocardial infarction has less benefitial effect on the improvement of late phase left ventricular function,and it may be because the insufficient reperfusion or reperfusion injury to myocardium but not the viable myocardium contributing to the poor result. Objectives To compare the different effects of late successful reperfusion with PCI on left ventricular function and its relationship with viable myocardium after acute anterior wall myocardial infarction in patients with or without diabetes. Methods A total of 125 consecutive subjects with acute anterior wall myocardial infarction were selected , and divided into diabetes mellitus (DM) group (n = 43) and Non-DM group (n = 82) according to WHO diabetes diagnosis criteria. All patients received successful PCI at 12 ± 8 days from onset. with low-dose dobutamine echocardiography, and left ventricular function and wall motion abnormality were also assessed with echocardiography before PCI. The data of clinical manifestations and angiograms before and after PCI were analyzed. Levels of creatinine kinase-MB (CK-MB), and Troponin T (TnT) before PCI, 6 hours and 24 hours after PCI were assessed. All patients received clinic and echocardiography follow-up for 6 months. Resul ts Higher rate of TIMI 2 flow, and lower rate of TIMI 3 flow in DM group were demonstrated immediately after PCI, and the rate of serum CK-MB and / or TnT levels were higher in DM group, compared with Non-DM group ( 63% of DM patients and 56% of non-DM patients were viable myocardium before PCI (P> 0.05). There were no significant differences of left ventricular ejection fraction (LVEF), left ventricular end diastolic volume index ( LVEDVI), left ventricular end systolic volume index (LVESVI), and wall motion score (WMS) between two groups at baseline before PCI (P> 0.05) .After six months, WMS was decreased and LVEF was increased in Non-DM group, but the WMS and the LVEF did not changed, and the LVEDVI was increased in the DM group compared with baseline; the LVEDVI, LVESVI, LVEF, and WMS were significantly different between the two groups (P <0.05 or P <0.01) non-diabetics, delayed successful revascularization with PCI in diabetics patient with acute myocardial infarction has less benefitia leffect on the improvement of late phase left ventricular function, and and it may be the insufficient reperfusion or reperfusion injury to myocardium but not the viable myocardium contributing to the poor result.