Aim of the study The aim is to assess the efficacy of the strategy of sodium bicarbonate 154mEq/l + glucose solution 5% (infusion rate: 3 mL • kg-1 • h-1 for 1 hour followed by 1 mL • kg-1 • h-1 for 6 hours) and NAC (1200 mg i.v. followed by 1200 mg bid for the next 48 hours) in reducing the incidence of CIN in patients with STEMI undergoing primary or rescue PCI. As control group, a population of STEMI patients treated with NAC (1200 mg i.v. followed by 1200 mg bid for the next 48 hours) + conventional hydration with saline solution 0.9% will be retrospectively enrolled. According to the common definition, CIN will be defined as increase of the level of serum creatinine >0,5 mg/dL and/or increase ≥25% serum creatinine and/or decrease ≥25% of the glomerular filtration rate (GFR) as calculated with the MDRD Modification of Diet in Renal Disease)formula at 48 hours after PCI compared with baseline value after primary PCI.