Objective Bone-marrow stem-cell transplantation has been shown to improve cardiac function in patients with AMI, but the safety of intracoronory infusion of autologous peripheral blood stem-cell(PBSCs) in patients with AMI is unknown. For this reason, we observe the feasibility and safety of PBSCs transplantation by intracoronory infusion in such patients.Method Fourty one patients with AMI were allocated to receive Granulocyte Colony-Stimulating Factor (G-CSF:Filgrastim,300 μg) with the dose of 300 μg-600 μg/day to mobilize the stem cell, and the duration of applying G-CSF was 5 days . On the sixth day, PBSCs were separated by Baxter CS 3000 blood cell separator into suspend liquid 57 ml. Then the suspend liquid was infused into the infarct related artery (IRA)by occluding the over the wire balloon and infusing artery through balloon center lumen. In the process of the intracoronary infusion of PBSCs, the complications should be observed, which were arrhythmias including of bradycardia, sinus arrest or atrial ventricular block, premature ventricular beats ,ventricular tachycardia, ventricular fibrillation; and hypotention, etc. Results There were total 10 cases with complications during the intracoronary infusion of PBSCs. The incidence of complications was 24.4%(10/41), including bradycardia is 2.4 %(1/41), sinus arrest or atrial ventricular block is 4.9%(2/41), ventricular fibrillation is 2.4 %( 1/41), hypotention is14.6 % (6 /41).Conclusions In patients with AMI, intracoronary infusion of PBSCs is feasible and safe. Objective Bone-marrow stem-cell transplantation has been shown to improve cardiac function in patients with AMI, but the safety of intracoronory infusion of autologous peripheral blood stem-cells (PBSCs) in patients with AMI is unknown. For this reason, we observe the feasibility and safety of PBSCs transplantation by intracoronory infusion in such patients. Method Fourty one patients with AMI were allocated to receive Granulocyte Colony-Stimulating Factor (G-CSF: Filgrastim, 300 μg) with the dose of 300 μg-600 μg / day to mobilize the stem cell, and the duration of applying G-CSF was 5 days. On the sixth day, PBSCs were separated by Baxter CS 3000 blood cell separator into suspend liquid 57 ml. Then the suspend liquid was infused into the infarct related artery ( IRA) by occluding the over the wire balloon and infusing artery through balloon center lumen. In the process of the intracoronary infusion of PBSCs, the complications should be observed, which were arrhythmias including of b radycardia, sinus arrest or atrial ventricular block, premature ventricular beats, ventricular tachycardia, ventricular fibrillation; and hypotention, etc. Results There were total 10 cases with complications during the intracoronary infusion of PBSCs. The incidence of complications was 24.4% (10/41 ), bradycardia was 2.4% (1/41), sinus arrest or atrial ventricular block was 4.9% (2/41), ventricular fibrillation was 2.4% (1/41) and hypotention was 14.6% (6/41). Conclusions In patients with AMI, intracoronary infusion of PBSCs is feasible and safe.