The aim of this study is to compare the effectiveness of four different strategies for preventing the ventricular postinfarction remodelling: 1) Conventional treatment for reperfunded extensive acute myocardial infarction, 2) Autologous bone marrow stem-cells intracoronary transplantation 3) mobilization of bone marrow stem-cells induced by granulocyte colony-stimulating factors (G-CSF); and 4) combined treatment (stem-cells transplantation plus mobilization with G-CSF).