Abstract: Objective:To investigate the effects of high dose atorvastatin on blood endothelial progenitor cells(EPCs) mobilization,and expression levels of vascular endothelial growth factor(VEGF) and toll like receptor 4(TLR4) in acute myocardial infarction(AMI) patients treated with percutaneous coronary intervention(PCI).Methods:One hundred emergency patients with AMI were randomly divided into the high dose group and conventional dose group(50 cases each group),and 50 patients with non-organic heart disease were set as the control group.The levels of EPCs,VEGF and TLR4 in three groups were analyzed.Results:After treatment,the EPCs amount and VEGF level in high dose group were significantly higher than those in conventional dose group(P<0.05 to P<0.01),and the level of TLR4 in high dose group was significantly lower than that in conventional dose group(P<0.01).Compared with before treatment,the EPCs amount and VEGF level significantly increased(P<0.01),and the level of TLR4 significantly decreased in high dose group(P<0.01).Compared with before treatment,the level of TLR4 significantly decreased(P<0.01),and the changes of the EPCs amount and VEGF level were not obvious in conventional dose group(P>0.05).After tre atment,the differences of the incidence rate of MVA and increasing rate of alanine aminotransferase between high dose group and conventional dose group were not statistically significant(P>0.05).Conclusions:High dose atorvastatin can increase the VEGF expression,mobilize bone marrow EPCs to repair the vascular intima,reduce TLR4 expression in peripheral blood monocytes,and play a role in inhibiting inflammation and stabilizing plaque.