Myocardial infarction and subsequent heart failure can be viewed as diseases of cellular deficiency. Cellular cardiomyoplasty is evolving as a promising therapy. Most studies have used cardiac or skeletal myocytes and each cell type has advantages as well as disadvantages, with impact on survival and integration. Cardiomyocytes are poor survivors in the injured heart, however, they are capable of forming electromechanical junctions with the host. In contrast, the more ischemia-resistant skeletal myoblasts survive much better in the injured myocardium, but their differentiated phenotype precludes formation of electromechanical junctions. Heat shocking graft cells prior to implantation significantly improves survival of both cell types. Genetic modification of the graft cells may further foster survival, and also may allow skeletal myocytes to better integrate with the host myocardium...