Role of stem cell therapy in the surgical treatment of heart failure

Direct intramyocardial stem cell transplantation is entering clinical practice for the surgical treatment of heart failure. Relying on experience gained from Phase I and Phase II clinical trials with intramyocardial transplantation of autologous bone marrow stem cells, we report here on the current knowledge of this new"cell-based" therapeutic option in the cardiac surgeon's hand. The underlying mechanisms of cardiac regeneration by stem cells transplantation, as currently postulated, are presented and new ways of delivery, including the surgical"stand alone" stem cell treatment, are discussed. Further- more, the possible beneficial effects of cardiac cell therapy in non-ischemic heart disease and its impact in the clinical bridge-to-transplant scenario are discussed. Finally, we provide evidence for the immunomodulatory effects of transplanted bone marrow stem cells and their possible impact in solid organ transplantation.