Effects of Melatonin on Cardiac Injury and Inflammatory Biomarkers in Patients Undergoing Coronary Artery Bypass Graft Surgery: a Meta-analysis

INTRODUCTION: The antiinflammatory and antioxidative effects of melatonin have been established in recent years. Several studies indicate that oxidative stress and inflammation are key drivers of post-coronary artery bypass graft (CABG) surgery complications. In the present study, we aimed to investigate the effects of melatonin on cardiac injury and inflammatory biomarkers in CABG candidates. METHODS: Embase, Medline/PubMed, Web of Science, Scopus, and the Cochrane library were searched up to 5 June 2022. All randomized controlled trials examining cardiac injury and inflammatory biomarkers of CABG patients who received melatonin were included. The random-effects model was utilized to perform the analysis. RESULTS: A total of 947 citations were retrieved through database searches. Finally, five articles (six trials with 342 patients) were included after the screening. Melatonin supplementation led to a significant reduction in cardiac troponin I (CTnI) [weighted mean difference(WMD): −2.28 ng/ml; 95% CI −2.87, −1.69; P < 0.01; I(2): 91.25%] and high sensitivity-C reactive protein (hs-CRP) levels (WMD: −0.62 mg/L; 95% CI −0.73, −0.5; P < 0.01; I(2): 99.98%) in patients undergoing CABG surgery. We found a nonsignificant decrease in creatine kinase isoenzyme muscle/brain (CK-MB) levels (WMD: −2.87 ng/ml; 95% CI −5.97, 0.23; P = 0.07; I(2): 99.98%) after melatonin supplementation. No publication bias was found according to Egger’s test. CONCLUSION: Melatonin supplementation may be useful in reducing cardiac injury and inflammatory biomarkers in CABG candidates. Future studies should investigate the clinical significance of these findings. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s40119-022-00287-1.