Abstract
BACKGROUND: Acute coronary syndrome (ACS) remains one of the leading causes of mortality worldwide. This study investigates the diagnostic and prognostic value of circulating exosomal miR-20b-5p and miR-1273g-3p in ACS. METHODS: This retrospective study randomly included 138 patients diagnosed with ACS according to the 2020 European Society of Cardiology (ESC) Guidelines for managing ACSs and 129 controls with normal coronary arteries (NCA) between October 2020 and November 2023 in Meizhou People's Hospital. Plasma-derived exosomes were isolated from patients with ACS and NCA controls. The expression of miR-20b-5p and miR-1273g-3p was measured using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Major adverse cardiovascular events (MACEs) within 1 year after percutaneous coronary intervention (PCI) were recorded. Receiver operating characteristic (ROC) curve analysis was carried out to assess diagnostic performance, and Kaplan-Meier survival analysis with Cox regression was applied to examine association of exosomal miR-20b-5p with MACEs. RESULTS: Both exosomal miR-20b-5p and miR-1273g-3p were markedly elevated in patients compared with NCA controls. The ROC analysis yielded an area under the curve (AUC) of 0.705 [95% confidence interval (CI): 0.639-0.771] for miR-20b-5p and 0.720 (95% CI: 0.657-0.783) for miR-1273g-3p, both slightly lower than that of cardiac troponin I (cTnI) (AUC =0.761; 95% CI: 0.693-0.829). Combined detection of cTnI with miR-20b-5p and miR-1273g-3p achieved AUCs of 0.818 (95% CI: 0.764-0.871) and 0.794 (95% CI: 0.737-0.850), respectively. During follow-up, patients with elevated miR-20b-5p levels exhibited a significantly higher incidence of MACEs. Multivariable Cox regression confirmed an independent association between miR-20b-5p expression and MACEs, with a hazard ratio of 3.107 (95% CI: 1.157-8.340, P=0.02). CONCLUSIONS: Exosomal miR-20b-5p and miR-1273g-3p represent potential diagnostic biomarkers for ACS, and miR-20b-5p also provides prognostic value for predicting MACEs.