Abstract
Myoblast transplantation is a promising new treatment for patients with congestive heart failure or myocardial infarction. Successful autologous myoblast transplantation to the myocardium has been demonstrated in a variety of animal models, where survival and engraftment of the injected myoblasts was verified by the presence of labeled skeletal cells4 and multinucleated myotubules characteristic of skeletal muscle in myocardial tissue. After injection into a damaged myocardium, skeletal myoblasts can differentiate and develop into striated cells, becoming integrated into the scar. More importantly, transplantation of myoblasts is correlated with improved myocardial performance. Taylor and colleagues2 demonstrated improved cardiac performance after transplanting autologous myoblasts into 12 cryoinjured rabbit hearts. More recently, autologous myoblast transplantation has been applied as an adjunct to coronary artery bypass grafting in humans with severe ischemic heart failure. In their early report, Menasché et al. reported successful autologous myoblast transplantation associated with concurrent improvement in myocardial function. In this study, myoblasts were delivered by direct injection into the epicardial surface of the infarcted myocardium during a thoracotomy for bypass surgery. While surgical transplantation of myoblasts into injured myocardium appears promising, a less invasive means of delivering the myoblasts would be preferable. In this preliminary report, we evaluated the feasibility of injecting skeletal myoblasts into infarcted porcine heart via a percutaneous endocardial delivery approach. Our objectives were to histologically confirm endoventricular delivery and engraftment of myoblasts into the damaged myocardium >1 week after injection. © 2006 Springer Science+Business Media, Inc.