Cardiovascular Diseases (CD) are currently one of the most common causes of death. Because heart related deaths occur on such an enormous scale this phenomenon is referred to as an epidemic. Chronic and acute injury of the heart could be an effect of cardiac remodeling, which is a result of molecular, cellular and interstitial changes, influenced by hemodynamic load or neurohormonal activation (Cohn et al., 2000). These small deviations in cardiac activity and morphology may lead to an enormous negative effect. Despite a significant progress, knowledge of standard risk factors for cardiovascular diseases has become less and less effective, which is why predicting and seeking an appropriate treatment is very challenging. As a result, there is a growing interest in finding new markers of the CD. MicroRNAs (miRNAs), are short, non-coding RNAs responsible for regulation of gene expression at the post-transcriptional level. Among them that have the greatest potential are microRNA molecules that circulate in the blood plasma or serum, that are related to direct activation of signaling pathways, implicated in the aging process and thus for the development of cardiovascular disease. This paper is a summary of the current state of knowledge on miRNAs, their biogenesis and potential role as biomarkers to diagnose heart disease.