The purpose of this study is to demonstrate that Iodixanol 320 is associated with a lower incidence of contrast-induced nephropathy (CIN) when compared with hyperosmolar contrast medium Iomeprol 350 in patients with impaired renal function undergoing percutaneous coronary interventions (PCI).

Iodixanol, an iso-osmolar, dimeric, non-ionic contrast agent has been shown to reduce the risk of developing CIN in patients with elevated serum creatinine concentrations compared to low-osmolar contrast agents. However, no information is available about a potential protective effect of Iodixanol in patients with impaired renal function on CIN when used during PCI. Due to the high volume of contrast exposition, patients with impaired renal function are at increased risk for the development of CIN compared to patients with normal excretory renal function.

The purpose of the investigation is to determine the changes of renal function in patients with impaired renal function receiving Iodixanol 320 or Iomeprol 350 for percutaneous coronary intervention.

Inclusion Criteria:

• chronic renal failure
• Informed, written consent

Exclusion Criteria:

• Cardiogenic shock
• Dialysis
• kidney transplantation
• Concurrent intake of nephrotoxic medication
• Planned or proceeded parenteral (i.v. or i.a.) administration of iodine-containing contrast medium at least 7 days before/after catheterization.
• Contra-indications for the use of Iodixanol (e.g. allergies)
• Women who are known to be pregnant, who are of childbearing potential and test positive for pregnancy, who have given birth within the last 90 days, who are breastfeeding
• Patient's inability to fully cooperate with the study protocol.
• Previous enrollment in this trial