BackgroundGrafting vessel with LIMA to the left anterior descending coronary artery plays a most important role in the long-term prognosis of OPCABG surgery. The aim of this study was to compare the effects of isoflurane preconditioning on miRs and mRNAs levels in the left internal mammary arterie (LIMA) graft with propofol in patients undergoing off-pump coronary artery bypass surgery (OPCABG).MethodsPatients were randomly assigned to receive either propofol (n=15), or interrupted isoflurane (n=15). In group P, propofol administration was continued at 3-5mg/kg/h intravenous injection for the duration of surgery. Five minutes prior to incision, patients of the isoflurane group (group Iso) received 2cycles of 1 MAC isoflurane.ResultsmiR-221 were significantly lower in group Iso (P<0 .05). E-selectin mRNA, RhoA mRNA and ROK mRNA were significantly lower at specimens of LIMA in group Iso compared with those in group P patients (P<0 .05). The expression of NOS3 mRNA was significantly higher in group Iso patients (P<0 .05).ConclusionOur findings provide some insight that prior interrupted isoflurane administration could regulate miR-221, and downstream effectors (mRNAs) and resulted in actual attenuation of inflammation and spasm of LIMA in patients undergoing OPCABG surgery.Trial registrationNCT No. (ClinicalTrials.gov): NCT02678650; Registration date: January 23, 2016.