ABSTRACT
After myocardial infarction, injured cardiomyocytes are replaced by fibrotic tissue promoting the development of heart failure. Stem cells are multipotent, undifferentiated cells capable of multiplication and differentiation. Preliminary experimental evidence suggests that stem cells derived from embryonic or adult tissues [especially bone marrow] may develop into myocardial cells. The overall clinical experience also suggests that stem cell therapy can be safely performed, if the right cell type is used in the right clinical setting. Preliminary efficacy data indicate that stem cells have the potential to enhance myocardial perfusion and/or contractile performance in patients with acute myocardial infarction, advanced coronary artery disease, and chronic heart failure. However, at the present time, the results have been mixed and inconclusive, and the mechanism of stem cell transplantation therapy remains unclear. This review discusses the controversies and problems that need to be addressed in future investigations