OBJECTIVE: To identify long-term outcomes and safety of transplantation of autologous peripheral blood stem cells (PBSC) for treating dilated cardiomyopathy.METHODS: A total of 38 cases with dilated cardiomyopathy received treatment at the Department of Cardiology, Guangdong General Hospital of Chinese People's Armed Police Forces, were selected, including 26 males and 12 females, aged 42-72 years, mean aged 56 years. Based on given standard therapy, 38 patients divided randomly into the transplantation group (n=20) and the control group (n=18). Patients in the transplantation group were received recombinant human granulocyte colony-stimulating factor (rhG-CSF) 300 ug/d once per day for 5 days to mobilize stem cells. At day 6, PBSC were collected with blood-cells separator and were transplanted through intracoroary way. The routine medication was performed in the control group. Blood routine test, hepatic function, renal function, glucose, triglyeride (TG), cholesterol, low density cholesterol (C-LDL), high density cholest- erol (C-HDL), uric acid (UA), creatine kinase (CK), isoenzyme of creatine kinase (CK-MB) and high sensitive C-reactive protein (hsCRP) were measured before and at months 6 and 12 after transplantation. All patients also received ultrasonic echocardiography, ECG Holter monitor and six-minute-walk test before and at 12 and 24 months after the procedure. Survival rate and incidence rate of heart incidents were compared. The study end-point was death from any cause. RESULTS: All patients received a 12-24 month follow-up with mean (18±6) months. One patient in the transplantation group received mitral valve replacement. One patient of the transplantation group and 2 of the control group died due to refractory heart failure. The blood routine test and biochemical indicators of the transplantation group had no significant differences among 6 months and 12 months after transplantation compared with control and pre-transplantation (P > 0.05). Six-minute-walking distance in the transplantation group significantly increased at 12 months after transplantation than pre-transplantation level, which was also higher than that of control patients (P < 0.05). The left ventricular ejection fraction (LVEF) was increased (P < 0.01). The left ventricular diastolic diameter (LVDd) decreased significantly in the transplantation group (P < 0.01). In the control group, improvement in LVEF and LVDd were observed, but there was no significant difference (P > 0.05). After 24 months of follow-up, the above-mentioned indexes had not improved in the transplantation group without significant differences. No malignant arrhythmias and severe side effects could be observed around transplantation and during 24 months follow-up. Survival was similar between the two groups during 24 months follow. CONCLUSION: Transplantation of mobilized autologous PBSC might be a safe and effective method for the treatment of dilated cardiomyopathy, which may improve the ventricular systolic function in a short-term, however, the long-term effects still uncertain.