Cellular therapy for myocardial repair

Post infarction left ventricular remodeling is a compensatory response to an acute myocardial infarction that is characterized by left ventricular dilation and myocardial hypertrophy. Although stable left ventricular remodeling may be achieved for a period of time, progressive myocardial dysfunction usually develops and ultimately leads to overt congestive heart failure. Heart failure is considered an end-stage, irreversible clinical condition for which current medical management strategies merely relieve symptoms, slow deterioration, and prolong life modestly. In recent years, stem cell transplantation has emerged as a potential "preventive" therapy for detrimental ventricular remodeling and progression to heart failure. The therapeutic approach is based on the notion that stem or progenitor cells can be delivered to the site of injury to directly or indirectly instigate repair of the damaged myocardium. This novel approach offers an unprecedented opportunity to treat the underlying loss of myocytes, restore function to the scar tissue in the infarct region and inhibit the cascade of events leading to congestive heart failure. This review focuses on recent research in the field of adult stem cell-based cellular therapy. In addition, stem cell mobilization with cytokines and growth factors to initiate endogenous repair of the infarct region is briefly discussed. Although cellular therapy shows great clinical promise, many hurdles remain before the possibility of widespread clinical use. However, the intense research efforts will likely lead to the development of effective cellular therapies against cardiovascular and other degenerative diseases.