MicroRNAs in cardiac arrhythmias: Mechanisms, biomarkers, and therapeutic frontiers

MicroRNAs (miRNAs) are essential modulators of cardiac arrhythmias, influencing electrical remodeling, ion channel dynamics, and fibrosis. Dysregulated miRNAs, including miR-1, miR-21, and miR-328, contribute to arrhythmogenesis through altered ion channel expression, heightened fibrosis, and inflammation. Recent investigations have identified novel circulating miRNA signatures-such as hsa-miR-96-5p and hsa-miR-184 for post-operative atrial fibrillation (POAF) post-coronary artery bypass grafting, offering high predictive accuracy and targeting pathways like MAPK and TGF-β, as revealed by biological pathway analysis. These miRNAs serve as noninvasive biomarkers for early risk assessment. Therapeutically, miRNA inhibitors and mimics, enhanced by nanoparticle and viral vector delivery, provide targeted interventions. Despite challenges in specificity and delivery, miRNA-based approaches hold transformative potential for arrhythmia diagnosis and personalized management.