The stem cell transplantation is emerging as a potential therapeutic modality for patients with heart failure. It has been demonstrated that intracoronary stem cell transplantation had beneficial effects on left ventricular perfusion and contractile functions. We hypothesized that patients with end-stage ischemic cardiomyopathy, who are candidates for heart transplantation, could also benefit from autologous intracoronary stem cell transplantation. We performed a prospective, open-labeled study in 10 patients with end-stage ischemic cardiomyopathy, who were on the waiting list for heart transplantation. Each patient received bone marrow-derived mononuclear cell infusion via balloon catheter in the target vessel, which had been revascularized by percutaneous intervention and was patent before the procedure. Clinical and laboratory evaluations, a treadmill exercise test, echocardiography, and single photon emission tomography (SPECT) were performed to the patients at baseline and 6 months after stem cell infusion. At 6-month follow-up of the eight patients who were able to complete the study, we revealed a significant increase in ejection fraction (from 30.0 +/- 6.6% to 36.2 +/- 7.3%; p = 0.001) in echocardiographic evaluation. SPECT evaluation also displayed a reduction in infarct area (50.4 +/- 16.1% to 44.1 +/- 12.5%; p = 0.003). Both myocardial oxygen consumption (p = 0.001) and metabolic equivalents (p = 0.001) were significantly increased at 6-month follow-up. These results demonstrate that intracoronary stem cell transplantation ameliorates heart failure symptoms and improves left ventricular function and perfusion. Therefore intracoronary stem cell transplantation may be used as an alternative treatment option for heart transplant candidates. - cellular cardiomyoplasty; heart transplant candidates; intracoronary infusion; stem cells; ischemic cardiomyopathy. (c) 2007 Tohoku University Medical Press.