Role of molecular imaging in stem cell therapy for myocardial restoration

During the past two decades, stem cells have created enthusiasm as a regenerative therapy for ischemic heart disease. Transplantation of bone marrow stem cells, skeletal myoblasts, and endothelial progenitor cells has shown to improve myocardial function after infarction. Recently, attention has focused on the potential use of embryonic stem cells and induced pluripotent stem cells because they possess the capacity to differentiate into various cell types, including cardiac and endothelial cells. Clinical trials have shown positive effects on the functional recovery of heart after myocardial infarction and have answered questions on timing, dosage, and cell delivery route of stem cells such as those derived from bone marrow. Despite the current advances in stem cell research, one main hurdle remains the lack of reliable information about the fate of cell engraftment, survival, and proliferation after transplantation. This review discusses the different cell types used in cardiac cell therapy as well as molecular imaging modalities relevant to survival issues.