Consecutive patients with chronic kidney disease, referred to our institutions for coronary and/or peripheral procedures, will be randomly assigned to 1) prophylactic administration of sodium bicarbonate plus NAC (Systemic alone therapy group; n > 133) and 2) RenalGuard System treatment (RenalGuard group; n > 133). All enrolled patients must have an estimated glomerular filtration rate <30 ml/min/1.73 m2 and/or a contrast nephropathy risk score ≥11). In all cases iodixanol (an iso-osmolar, non ionic contrast agent) will be administered. The primary end point is an increase of >=0.3 mg/dL in the creatinine concentration 48 hours after the procedure.