effect of melatonin on cardiac injury after primary percutaneous coronary intervention: a randomized controlled trial

several studies have reported that the antioxidant properties of melatonin can provide cardiac protection through scavenging of free radicals. this study sought to investigate the efficacy of melatonin on cardiac biomarkers, myocardial-specific protein high sensitive troponin-t (hs-tnt) and creatine kinase-mb (ck-mb), in patients with st-segment elevation myocardial infarction (stemi) undergoing primary percutaneous coronary intervention (ppci). in this randomized clinical trial, a total of 40 patients with stemi planned to undergo ppci were randomly assigned to two groups of receiving melatonin plus standard treatment [n=20] and control group, receiving only standard therapy [n=20]. the following parameters including hstnt and ck-mb were assessed preoperatively (baseline) and at six hours after procedure. melatonin could significantly reduce the level of ck-mb (118.2 ± 21.09 iu/l in the treated group versus 198.24 ± 20.94 iu/l in the control group; p value = 0.01). however, there was no difference in the mean hs-tnt level between two groups (2491 ± 664 μg/l vs. 2801 ± 620 μg/l; p value = 0.73). our results revealed that melatonin can be considered as a safe adjunctive medication to the standard regimen after ppci for the aim of decreasing cardiovascular events. meanwhile, this was a pilot study with a small number of patients and further studies are needed to confirm the beneficial effect of melatonin in patients with stemi.