Study of micro-RNA regulatory networks (known as miRNA’s or miR’s), during development and in known pathologies have been the basis of study over the past decades. Herein, we recapitulate these findings in order to highlight the best underlying mechanisms found to date. We also seek to elucidate how miRNA dysregulation can be associated with many cardiovascular diseases. Furthermore, we discuss miR regulation mechanism during in early development in vivo and invitro. Since many of the miR’s are precursors to transcriptional regulation, we relate back to their molecular control as we can then look together at the fundamental disease they might be exacerbating by this dysregulation.