Abstract—There have been tremendous advances since past decade in the field of regeneration medicines with a hope of having potential to improve recovery from the most widespread diseases; cardiovascular disorder is one of them. Since then continuous preclinical and clinical trials have allowed to identify some important issues such as immune rejection, number of cells required, route of administration, engraftment, etc. These are to be addressed by appropriately focused bench work to find out a stem cell source having prerequisites as easily available, phenotypically well characterized, genotypically stable, consistent, scalable and sterile for an effective therapeutic application. In the current investigation we tested whether MSCs isolated from two fetal tissue sources such as Wharton's jelly and Umbilical cord blood can be coaxed in vitro into cardiomyogenic lineages with the exposure to 5' Azacytidine and whether regeneration of in vivo mouse myocardial infarcted heart is triggered by transplantation of these differentiated cells. Cardiac progenitor formation from guided in vitro MSC differentiation is the major determinant of in vivo cardiac regeneration in murine model. We could also observe that Wharton's Jelly is more potent source as compared to cord blood as far as extent of cardiac regeneration is considered.