From CK-MB to MicroRNAs: Evolving Biomarker Strategies for Early Diagnosis of Myocardial Infarction
Abstract
Myocardial infarction (MI) remains a major cause of morbidity and mortality worldwide, and accurate early diagnosis iscritical to improving clinical outcomes. High-sensitivity cardiac troponins (hs-cTn) are the current gold standard biomarkersdue to their excellent sensitivity, yet they have limitations including delayed elevation in very early infarction and reducedspecificity in patients with renal dysfunction or non-ischemic myocardial injury. This systematic review evaluated thediagnostic performance of traditional biomarkers (CK, CK-MB, myoglobin, hs-cTn) and emerging molecular approachesincluding circulating microRNAs (miRNAs) and multi-marker strategies. Seven studies and one meta-analysis wereincluded, encompassing over 23,000 patients. Classical biomarkers such as CK and CK-MB demonstrated limited sensitivitybut retained niche value in peri-procedural MI due to higher specificity, with CK-MB achieving up to 96% specificity.High-sensitivity troponins provided superior early detection with sensitivities approaching 90% but showed reducedpositive predictive value in unselected emergency department populations. Circulating miRNAs, particularly miR-499 andmiR-133a, achieved pooled sensitivities and specificities around 0.88, highlighting their potential for ultra-early MI detection.Furthermore, computational models like the ARTEMIS algorithm integrating hs-cTn with clinical variables achieved AUCsof 0.92–0.98, surpassing traditional threshold-based diagnostics and enabling personalized probability-based assessment.Overall, the findings suggest that while hs-cTn remains the primary diagnostic biomarker, combining it with molecularmarkers and advanced computational models can improve early diagnosis, specificity, and clinical decision-making inmyocardial infarction.