Study Objectives: To determine whether, in patients with large acute myocardial infarction undergoing primary or rescue angioplasty, the administration of subcutaneous Lenograstim [recombinant human Granulocyte-Colony Stimulating Factor (rhu G-CSF), Myelostim 34, Italfarmaco] associated with Myocardial Contrast Echocardiography and the intravenous infusion of sulphur hexafluoride (Sonovue, Bracco) determines an improvement: