Abstract

Current perspective of stem cell therapies for cardiac regeneration

Author(s): Yee Ki Lee, Chung-Wah Siu, Yang Zhang and Hung-Fat Tse

Despite recent advances in prevention and treatment of coronary artery disease, it remains the major cause of morbidity and mortality worldwide. There is an unmet need for treatment of ischemic cardiomyopathy caused by postmyocardial infarction, left ventricular remodeling or chronic myocardial ischemia. As a result, there is tremendous interest in developing stem cell therapies for prevention and treatment of ischemic cardiomyopathy. Although the mechanism remains unclear, the majority of preclinical studies demonstrate that different sources of cell-based therapy reduce the infarct size, and improve myocardial perfusion and contractile function. Recent results from randomized controlled clinical trials suggest that intracoronary or intramyocardial injection of bone marrow-derived cells may be a safe and feasible strategy for treatment of acute myocardial infarction as well as chronic myocardial ischemia. Furthermore, these studies have also provided initial evidence of clinical efficacy with modest, but significant improvement in left ventricular ejection fraction and functional status. However, most of these studies are limited by relatively small sample sizes and a short duration of follow-up, and the clinical efficacy of stem cell therapy in coronary artery disease needs to be confirmed by ongoing major clinical trials. In addition, further studies are also required to refine the optimal timing, cell types and mode of delivery, and to develop strategies to overcome the potential hurdles related to cell-based therapy.