Diagnostic and Prognostic Value of miRNAs after Coronary Artery Bypass Grafting: A Review

SIMPLE SUMMARY: Coronary artery bypass graft (CABG) surgery is a procedure in which complex coronary arteries stenosis is treated by bypassing atherosclerotic lesions with venous or arterial grafts. CABG is associated with myocardial damage due to ischemia/reperfusion injury. In addition, postoperative complications, including perioperative myocardial infarction, atrial fibrillation and graft failure, remain important clinical challenges. So far, no reliable diagnostic and prognostic tools to predict outcomes after CABG surgery have been established. MiRNAs are noncoding, 21–24 nucleotide-long RNA particles, expressions of which alter during CABG surgery. Here, we summarize the potential clinical applicability of miRNAs as promising biomarkers to predict post-CABG procedure outcomes. ABSTRACT: MiRNAs are noncoding, 21–24 nucleotide-long RNA particles that control over 60% of genes. MiRNAs affect gene expression through binding to the 3’-untranslated region of messenger RNA (mRNA), thus inhibiting mRNA translation or inducing mRNA degradation. MiRNAs have been associated with various cardiovascular diseases, including heart failure, hypertension, left ventricular hypertrophy, or ischemic heart disease. In addition, miRNA expression alters during coronary artery bypass grafting (CABG) surgery, which could be used to predict perioperative outcomes. CABG is an operation in which complex coronary arteries stenosis is treated by bypassing atherosclerotic lesions with venous or arterial grafts. Despite a very low perioperative mortality rate and excellent long-term survival, CABG is associated with postoperative complications, including reperfusion injury, graft failure, atrial fibrillation and perioperative myocardial infarction. So far, no reliable diagnostic and prognostic tools to predict prognosis after CABG have been developed. Changes in the perioperative miRNA expression levels could improve the diagnosis of post-CABG myocardial infarction and atrial fibrillation and could be used to stratify risk after CABG. Herein, we describe the expression changes of different subtypes of miRNAs during CABG and review the diagnostic and prognostic utility of miRNAs in patients undergoing CABG.