Stem cells for repair of the heart

Abstract

Stem cell therapy for treatment of cardiac disease has shown therapeutic potential. A number of stem and progenitor populations have been identified for potential use in cardiac repair. Each possesses a unique potency that justifies consideration for use. Autologous, unfractionated bone marrow cells or skeletal myoblasts were used in early clinical trails to evaluate reparative effects on recent or record infarcts. In each case, evidence of limited improvement in cardiac function was obtained. Myoblast grafts were unexpectedly correlated with arrhythmias, thereby identifying a safety issue. The small number of patients and the lack of randomized control groups preclude conclusions regarding efficacy. Randomized controlled, intermediate-sized, double-blind clinical trials must be undertaken to this end. Cellular therapy may be useful in the treatment of cardiac disease in adults. Appropriate adaptations to meet unique requirements for treatment of pediatric cardiovascular disease may be required. Bone marrow and skeletal myoblasts do not promote true tissue regeneration in spite of observed functional improvement. Trials using cells possessing true potential for (trans)differentiation may elucidate the potential and value of this therapy as a reparative modality. Development of optimal strategies for targeted delivery consistent with pathobiology is of exception clinical relevance.