Circulating MicroRNA profile in coronary artery disease

Background/Introduction Despite advancements in cardiovascular disease (CVD) prevention and management, coronary artery disease (CAD) remains a leading cause of global morbidity and mortality. Current risk prediction models are limited in accuracy due to genetic, environmental, and lifestyle variations, highlighting the need fornovel biomarkers. MicroRNAs (miRNAs), small non-coding RNAs that regulate gene expression, have emerged as potential diagnostic and prognostic biomarkers in CAD. Circulating miRNAs in plasma offer a non-invasive approach for early disease detection and risk stratification. However, their clinical utility remains underexplored. Purpose This study aimed to evaluate the circulating miRNA profile in patients with acute coronary syndrome (ACS) and chronic stable angina (CSA) compared to healthy controls. We sought to identify differentially expressed miRNAs and assess their diagnostic and prognostic potential in CAD. Methods This prospective observational study (January 2020–January 2022) at a tertiary care center investigated circulating miRNAs in acute coronary syndrome (ACS) and chronic stable angina (CSA) patients, compared to healthy controls. Exclusion criteria included severe comorbidities, liver/renal dysfunction, malignancy, or refusal to participate. Plasma miRNA expression was analyzed using qRT-PCR, with statistical tests and ROC curve analysis assessing diagnostic potential. Five CAD-related miRNAs (miR-92a, miR-126, miR-133a, miR-145, miR-155) were studied, with miR-16 as a reference. The intended sample size was 60, but due to COVID-19, only 21 participants (7 per group) were analyzed. Results CAD patients demonstrated distinct circulating miRNA profiles compared to healthy controls. MiRNA 133a was absent in all control subjects but expressed in 85.7% of ACS and CSA patients, highlighting its potential as a CAD biomarker. MicroRNA 92a was overexpressed in ACS and underexpressed in CSA, suggesting a role in differentiating CAD subtypes. Among traditional CAD risk factors, only Δ-Ct126 was significantly associated with dyslipidemia (p = 0.028), indicating prognostic relevance. ROC analysis confirmed microRNA 133a as a strong predictor of CAD (p < 0.001), while Δ-Ct145 showed potential but did not reach statistical significance. Conclusion Circulating miRNAs hold promise as novel biomarkers for CAD diagnosis and risk stratification. Their stability and non-invasive detection make them valuable candidates for future clinical applications. Large-scale validation studies are needed to confirm their utility and integrate miRNA-based assays into routine cardiovascular risk assessment.