Introduction:Periprocedural myocardial injury (PMI) following elective percutaneous coronary intervention (PCI) is an important therapeutic concern with remaining some mortality and morbidity. To the best of our knowledge, there is no published study that investigates the potential benefit of CoQ10 in preventing PMI following elective PCI. Methods:In a randomized, clinical trial, 100 patients who scheduled for elective PCI were allocated in to the intervention (n=50) and control group (n=50). The intervention received a 300 mg loading dose CoQ10 12 hours before procedure.The level of CK-MB and troponin-I was measured before procedure, and 8 and 24 hours after. Furthermore, hs-CRP was measured at baseline and 24 hours after.All patients were assessed for the incidence of major adverse cardiac effects (MACEs) after 1 month. Results:The CK-MB elevation (above the upper limit normal) was occurred in 22% (n=11) of CoQ10 and 20% (n=10) of control (P=.806). The elevation of troponin-I was documented in 8% (n=4) of both groups. No significant change in the level of cardiac biomarkers was noted. However, the significant reduction in hs-CRP level was occurred in CoQ10 group (P=.032). Conclusion:The results showed that pretreatment with 300 mg CoQ10 12 hours before procedure could not reduce PMI following elective PCI, however, significantly decreased hs-CRP. K E Y W O R D SCK-MB, CoQ10, hs-CRP, Percutaneous coronary intervention, Periprocedural myocardial injury, Troponin-I