Cardiovascular diseases (CVDs) have shown a high prevalence every year, presenting arterial hypertension as prime factor for their development, also driven by population growth, the aging of population and epidemiologic changes in disease. One of the main challenges in the study of CVD is the identification of reliable biomarkers that can be used in clinical practice and, in this context, microRNAs (miRNAs) have attracted much attention recently. MiRNAs are small non-coding RNAs, identified as post-transcriptional regulators of the expression of several genes both in physiologic and pathologic conditions. They have been studied as possible biomarkers, since they are highly expressed in the vascular system and are crucial modulators for the differentiation, contraction, migration and apoptosis of vascular cells, so modifications in their expression can cause several vascular alterations. Thus, this review aimed to compile the main studies regarding the role of miRNAs in the development of cardiac diseases, their potential applicability in the diagnosis, prognosis and treatment of these disorders. It was possible to verify that alterations in miRNAs expression are present in almost all cardiovascular diseases, such as the development of cardiac hypertrophy, coronary heart disease, heart failure and other conditions. Furthermore, growing evidence indicates that circulating miRNAs may become a potential tool for rapid and easy tests, since they are detected in peripheral blood, also allowing new therapeutic possibilities.