The Role of microRNAs in Cardiac Hypertrophy and Progression to Heart Failure

microRNAs (miRNAs) are small noncoding RNAs that regulate gene expression post-transcriptionally and play central roles in cardiac development, hypertrophy, fibrosis, apoptosis and remodelling. Evidence from animal models, human tissue and circulating biomarker studies implicates several cardiac-enriched and stress-regulated miRNAs (notably miR-21, miR-1, miR-133, miR-208 and the miR-132/212 cluster) in the pathogenesis of pathological hypertrophy and the transition to symptomatic heart failure (HF). Translational efforts include circulating miRNA biomarker studies and antisense oligonucleotide therapies (e.g., CDR132L targeting miR-132) that have advanced into early clinical trials. Despite promise, challenges remain for clinical application: tissue delivery, off-target effects, specificity of circulating signatures, and standardised assays. Continued mechanistic work and carefully designed clinical trials are required to validate miRNA-based diagnostics and therapeutics.