[Regeneration of infarcted cardiac tissue: the route of stem cells].

The ventricular remodeling following an acute myocardial infarction generates a non-contractile fibrous scare which might provoke cardiac failure. Several techniques aimed at recovering myocardial performance through the utilization of stem cells have been investigated in these last years. Embryonal stem cells, although they are characterized by an elevated differentiation potential, present technical and ethical concerns. Thus, most studies have been addressed towards adult (somatic) stem cells. Three categories of adult stem cells are now mainly investigated: a) satellite cells from skeletal muscle, b) mesenchymal stem cells from bone marrow, c) stem cells which are eventually present in the cardiac tissue. Skeletal myoblasts, even if they are not able to differentiate in cardiomyocytes, can improve cardiac contractility at the level of the fibrous scare which substitutes the necrotic area. It is also possible to isolate stem cells from bone marrow which can originate several cell lines, among them cardiac muscle cells and endothelial cells. Finally, more recent studies have demonstrated that resident cardiomyocytes maintain the capability to duplicate: therefore, a population of myocardial progenitors might be able to replicate and repair the damaged tissue. A deeper investigation of these findings in the clinical field could lead to the identification of new therapeutic strategies aimed at ameliorating the cardiac performance of the infarcted patients for short and long periods.