Copyright: © 2013 Parsons XH. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. To regrow the human heart had only been a dream, not a possibility before the derivation of human embryonic stem cells (hESC) from the inner cell mass (ICM) or epiblast of the human blastocyst [1,2]. In the adult heart, cardiomyocytes, the mature contracting cardiac muscle cells, are terminally differentiated and unable to divide. There is no evidence that stem/precursor/progenitor cells derived from mature tissues, such as bone marrow, cord blood, umbilical cord, mesenchymal stem cells, patients heart tissue, placenta, or fat tissue, are able to give rise to the contractile heart muscle cells following transplantation into the heart [1,2]. Despite numerous reports about cell populations expressing stem/precursor/progenitor cell markers identified in the adult hearts, the minuscule quantities and growing evidences indicating that they are not genuine heart cells and that they give rise predominantly to smooth muscle cells rather than functional cardiomyocytes have diminished any enthusiasm [1-3]. Therefore, there is mounting skepticism about the existence of endogenous human cardiac stem cells after birth. Derivation of hESCs in vitro from the IVF leftover embryos has brought a new era of cellular medicine for the heart [1,2]. The intrinsic ability of a hESC to both unlimited self-renew and differentiation into cardiac elements makes it a practically inexhaustible source of replacement cells for the damaged heart. The hESC cardiac cell therapy derivatives are emerging as a new type of pharmacologic agent of cellular entity in cellbased regenerative medicine because they have direct pharmacologic utility and capacity for human myocardial tissue reconstitution and contractile function restoration that the conventional compound drug of molecular entity lacks [1-6]. The pharmacologic activity of human cardiac stem cells is measured by their extraordinary cellular ability to regenerate the functional and structural cardiac tissue element, thus, the contractile cardiomyocytes that has been damaged or lost. Therefore, the pharmacologic utility of human cardiac stem cells cannot be satisfied only by their chaperone activity, if any, to differentiate into nonfunctional smooth muscle cells or endothelial cells, or produce trophic or protective molecules to rescue endogenous dying cardiomyocytes that can simply be achieved by a compound drug of molecular entity. Although a vast sum of government and private funding has been spent on looking for adult alternates, such as reprogramming and trans-differentiation of fibroblasts or mature tissues, so far, only human cardiac stem/precursor/progenitor cells derived from embryooriginated hESCs have shown such cellular pharmacologic utility and capacity adequate for myocardium regeneration in pharmaceutical development of stem cell therapy for the damaged heart [1-6].