Nephrotoxic risks of renal angiography: contrast media-associated nephrotoxicity and atheroembolism--a critical review.

Renal angiography remains the "gold standard" procedure for the detection of renal artery stenosis. However, clinicians often avoid renal angiography because of fears of contrast media-associated nephrotoxicity (CM-AN) and atheroembolism. This review focuses on these potential angiographic complications, with particular emphasis, in the case of CM-AN, on clinical features, incidence, risk factors with an emphasis on pre-existing renal insufficiency and diabetes mellitus, volume of contrast media, low osmolar versus high osmolar contrast media, and prophylaxis. For atheroembolism, areas emphasized are pathology, clinical features, precipitating features, and incidence in various settings. Although the literature contains an abundance of information about CM-AN and atheroembolism, this review identified multiple areas of uncertainty regarding features of both of these complications. For example, additional studies are needed to determine the incidence of CM-AN, both asymptomatic and clinically severe, in patients with a wide range of pre-existing renal insufficiency with and without diabetes mellitus, following low volume digital subtraction renal angiography with low osmolar contrast media. In a similar manner, studies are needed with adequate postcontrast observation periods to determine the true incidence of clinically significant atheroembolism following diagnostic renal angiography and angioplasty and techniques that may modify this complication. Until further knowledge in both of these areas is available, it is difficult to precisely determine the risks of renal angiography and/or angioplasty in the azotemic patient suspected of or having renal ischemic disease using modern radiologic techniques.