Contrast medium induced nephropathy: new insights into prevention and risk management

Diagnostic and interventional cardiac imaging modalities employing contrast media (CMs) have become increasingly widespread in the recent years, especially multi-slice coronary computed tomography (MSCCT) and percutaneous coronary intervention (PCI). Contrast medium induced nephropathy (CIN), defined as impairment of renal function within 48-72 hours after administering CM, is one of the most common causes of hospital acquired renal insufficiency. The overall incidence of CIN in the general population is low (0.6-2.3%), but it may become remarkably elevated in patients with pre-existing renal failure, diabetes mellitus and in the elderly, all of whom represent a large cohort of patients undergoing cardiac studies. Calculating a simple risk score that is based on readily available information can assess the overall risk of CIN in each individual patient. Volume supplementation in moderate-high risk patients remains the cornerstone for preventing CIN. The combination of oral volume overload and intravenous (i.v.) hydration with normal saline (NS) or bicarbonate significantly reduces the risk. Since no ideal CM exists, preventing CIN involves reducing the given volume, avoiding the use of high osmolality or high viscosity CM, and limiting repeated exposure. Several vasodilators have been tested and controversial results have been observed. Recently, considerable interest has arisen due to the initial positive data on the effectiveness of antioxidant agents in reducing CIN incidence. In this review, we focus on the current strategies in the risk management of CIN and on the effectiveness of new preventive pharmacological therapies.