Abstract

Stem Cell Therapy: A New Approach for Treatment of Myocardial Infarction

Ashton Faulkner and Paolo Madeddu

Stem cell therapy offers the opportunity of myocardial repair in patients who have suffered a myocardial infarction, a concept currently not feasible with present treatment options. Embryonic, adult, and induced pluripotent stem cells all offer a potential cell source for myocardial repair. Pre-clinical studies suggest that embryonic and induced pluripotent stem cells may be the most ideal cell type as they have the potential to differentiate into cardiomyocytes and restore a degree of functional recovery in animal models. Due to practical and ethical issues surrounding these cell types however, more focus has been on the use of adult stem cells, predominantly those of the bone-marrow. Pre-clinical studies suggest that bone-marrow stem cells can promote a degree of functional recovery through either differentiating into cardiomyocytes or acting in a paracrine manner to promote neoangiogenesis. The apparent success in pre-clinical models paved the way to a number of clinical trials to take place. Although mixed results have been reported, these trials have however shown that stem cell therapy is safe and feasible in humans. Many questions are still unanswered including, what is the optimal cell type, dose and timing of transplantation. This review highlights the benefits and limitations of each cell type and possible regenerative mechanisms.