The prevention of contrast-induced nephropathy in patients undergoing percutaneous coronary intervention.

Contrast-induced nephropathy (CIN) is a leading cause of morbidity and mortality in high-risk patients undergoing percutaneous coronary intervention (PCI) or other radiocontrast procedures. Approximately 25% of all patients selected for these procedures are at risk for its development. Patients who experience this complication have higher rates of mortality, longer hospital stays and poorer long-term outcomes. The occurrence of CIN is directly related to the number of co-existing clinical risk factors. Among the many risk factors, preexisting renal impairment, advanced age, the presence of diabetes mellitus and both the volume and type of the contrast agent administered are among the most important. While the precise pathophysiological mechanisms responsible for this condition are complex and incompletely understood, experimental studies suggest that the pathogenesis involves a combination of renal ischemia and direct tubular epithelial cell toxicity. At the present time, adequate periprocedural hydration and the selection of low-osmolar and, more recently, iso-osmolar contrasts agents are the only available tools to the operator for reducing the risk of this complication. Several other modalities, such as the use of NaHCO3 and hemofiltration, also appear promising in preventing the development of this complication. This article reviews the epidemiology, pathophysiology, and consequences of CIN. It also reviews the risk factors for the development of CIN, as well as the history of the various modalities studied in its prevention.