Effect of alpha-lipoic acid on atrial fibrillation and biomarkers of myocardial injury in patients undergoing coronary artery bypass surgery: study protocol of a randomized, double-blind, placebo-controlled clinical trial

<title>Abstract</title> <bold>Background</bold> : Coronary artery bypass grafting (CABG) is associated with several postoperative complications, notably atrial fibrillation (AF), which may arise due to myocardial reperfusion following ischemia and the resulting inflammatory response. Alpha-lipoic acid (ALA) is a potent antioxidant compound known for its ability to reduce oxidative stress and regenerate endogenous antioxidant defenses. The aim of this study is to investigate the effects of ALA supplementation on the incidence of AF and biomarkers of myocardial injury in patients undergoing CABG. <bold>Methods</bold> : In this randomized, placebo-controlled, parallel-design clinical trial, 50 eligible patients scheduled for CABG, will be randomly assigned into two groups to receive either 1200 mg/day ALA (ALA group, n=25) or placebo (control group, n=25), starting 10 days prior to surgery and continuing for five days after CABG. The occurrence of AF will be monitored using Holter monitoring during the first 72 hours after surgery and electrocardiography (EKG) performed three times daily on postoperative days four and five. Changes in complete blood count (CBC), troponin I, creatine kinase, muscle brain subunits (CK-MB), albumin, total protein, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) concentrations will be assessed at baseline, 24hr and five days after surgery. The length of hospital and intensive care unit (ICU) stay will be recorded. Echocardiography will be performed at baseline and on postoperative day five. Dietary intake will be assessed throughout the study period. <bold>Discussion</bold> : This trial is expected to provide valuable preliminary data on the effects of ALA supplementation in reducing post-CABG AF and myocardial injury. The findings may lay the groundwork for future research into the adjunctive use of ALA, alone or in combination with other antioxidants, to mitigate complications following CABG. <bold>Trial registration</bold> : The research protocol has been approved by the Bioethics Committee of Tehran University of Medical Sciences (No. IR.TUMS.THC.REC.1403.052). The trial protocol has also been registered with the Iranian Registry of Clinical Trials (IRCT20131125015536N16).