Liu W, et al. - In patients with stage C or D heart failure (HF), researchers investigated HF-specific circulating micro-RNAs (miRNA), as well as the possible correlation of the selected miRNAs with myocardial fibrosis. They also determined if the selected miRNAs indicated the incidence of adverse cardiovascular events in these patients. Using microarray analysis, they identified circulating miRNAs expressed in end-stage HF patients and matched healthy controls. For validation, quantitative real-time polymerase chain reaction was used. To determine the prognostic value of the selected circulating miRNAs in HF patients, they performed multivariate Cox regression analysis. Findings revealed a correlation of a circulation miRNA, miR-197-5P, with MF and adverse cardiac events in HF patients under the age of 50 years.