Objective: To investigate the effect of autologous angiogenin-overexpressing marrow stromal cells transplanted in a porcine model of chronic ischemia. Methods: Standard experimental pigs underwent placement of a left circumflex artery ameroid occluder and were randomized to treatment with marrow stromal cells transfected ex vivo by angiogenin gene (Group I, n=11), or with marrow stromal cells without any gene transfected (Group II, n=10), and an additional group of animals served as a control (Group III, n=10). Cells were cultured, ex vivo angiogenin gene transferred, labeled by CM-DiI and transplanted by directly operating epicardial injection . Rentrop score were evaluated by angiography analysis, and ejection factor by echocardiography after 4 weeks of the therapy. The percentage of infarct area, vessel density, angiogenin protein expression, CM-DiI labeled cells were also evaluated at the same time. Results: Group I revealed significantly greater improvement in the Rentrop score, ejection factor and showed the smaller infarction area and apparent more normal gross left ventricular geometry and wall thickness than the other groups. Di-I labeled cells were observed on fluorescence microscopy indicated the successful engraftment of marrow stromal cells in group I in contrast to the Group II, which showed only sporadic labeled cells. In Group I the protein expression of angiogenin by Western blot and vessel number were also significantly increased. Conclusion: Transplantation of autologous angiogenin-overexpressing marrow stromal cells increases the survival of implanted cells and improves the impair heart function.