Abstract: OBJECTIVE: To explore the cardiac protection effects of a single high loading dose of statins therapy before coronary artery bypass grafting (CABG) on cardiac specific miRNAs (miRNA-1, miRNA-133 miRNA-208 and miRNA-499). METHODS: Patients undergoing CABG were divided into two groups randomly 12 hours before cardiac operation: Group A, receiving standard-dose of 20mg atorvastatin; Group B, receiving single-dose of 80mg atorvastatin. 5 right atriums from group A and 3 from group B were achieved during the operation. Accompanied with 4 right atriums in healthy population as group C, the gene expression on cardiac specific miRNAs (miRNA-1, miRNA-133, miRNA-208 and miRNA-499) of the three groups were examined by a stem-loop quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). RESULTS: The expressions of cardiac specific miRNAs including miRNA-1, miRNA-133a, miRNA-133b, miRNA-208a, miRNA-208b, miRNA-499a-3p, miRNA-499a-5p and miRNA-499b-3p in group A, B and C were not significant changed. Strikingly, miRNA-499b-5p was significantly increased in group B comparing to both healthy group A(p=0.005) and group C (p=0.010). CONCLUSINS: The cardiac protection effect of a single high loading dose of statins therapy before CABG maybe related to elevated miRNA-499b-5p.