The long-term effect of intracoronary infusion of progenitor cells in patients with chronic ischemic cardiomyopathy. Bone marrow stem-cell administration in patients with myocardial infarction improved myocardial performance and in some studies contributed to favorable left ventricular remodeling. We report on the results of a pilot, single center, controlled safety, and feasibility study, including 24 patients with old, nonviable anterior myocardial infarction. Twelve patients underwent intracoronary administration of selected CD133(+) and CD133(-)CD34(+) progenitor cells and 12 were followed up on medical therapy. Left ventricular volumes and ejection fraction, at rest and during low-dose dobutamine, and myocardial viability, using TL-201 reinjection scintigraphy, were analyzed at baseline and long-term follow-up. Patients in the treatment group experienced a sustained decrease in left ventricular end-diastolic and end-systolic resting volumes (P = 0.008 and P = 0.002, respectively), as well as an improvement in global ejection fraction at rest [from (27.2 +/- 6.8)% to (29.7 +/- 7.3)%, P = 0.016]. Segmental anterior and apical wall perfusion, during TL-201 reinjection, were similarly improved (P = 0.005 and P < 0.001, respectively). One patient developed restenosis at the cell delivery site and one progression of atherosclerosis. During 28.0 +/- 8.7 months of clinical follow-up, only one patient experienced deterioration of heart failure. In the control group, we observed stability in the perfusion defect and deterioration in end-diastolic and end-systolic volumes (P= 0.002 and P = 0.003, respectively) and a nonsignificant decrease in ejection fraction (P = 0.11). Intracoronary infusion of selected CD133(+) and CD133(-)CD34(+) progenitor cells to a previously infarcted and nonviable anterior wall is safe, and results in sustained improvement in segmental myocardial perfusion and in favorable left ventricular remodeling. (c) 2007 Wiley-Liss, Inc.