Since the early 1990s, cellular cardiomyoplasty (or simply cell transplantation) has been explored as a potential new therapy to alleviate the consequences of myocardial infarction (MI)(1). Many different cell types have been tried (2) and, quite naturally, cardiomyocytes were chosen early on, reasoning that they would be the ideal replacement for lost cardiomyocytes (3, 4). Since these groundbreaking studies, several investigators have shown that cardiomyocytes can form viable grafts in and integrate with the host myocardium (5–8). However, there are several significant drawbacks to this cell type. The first problem stems from availability, that is, for today’s infarct patient and likely for the next several years, there is no feasible source of cardiomyocytes for clinical applications. Embryonic stem cells show the most promise for large scale cardiomyocyte production, but much basic research remains to be done with these cells before they could be used safely or effectively.