This discovery sparked the idea of regenerating the heart cells by taking the stem cells inside the heart and reprogrammed them into cardiac tissues.[7] The importance of these stem cells are: self-renewal, the ability to differentiate into cardiomyocytes, endothelial cells and smooth vascular muscle cells, and clonogenicity. These stem cells are capable of becoming myocytes, which are for stabilizing the topography of the intercellular components as well as to help control the size and shape of the heart, as well as vascular cells, which serves as a cell reservoir for the turnover and the maintenance of the mesenchymal tissues.[7] Ebryotic stem cells are shown to be able to form into other types of cells, however no clinical studies has used this for myocardial regeneration yet to avoid the possibility of the formation of teratoma. at the moment, autologous cells are the most used in clinical trials, such as bone marrow, to avoid tissue rejection.