Pitfalls in Imaging for Renal Artery Stenosis

Renal artery stenosis is recognized as an important cause of secondary hypertension. Particularly with atherosclerotic disease, renal artery stenosis can progress to threaten kidney function and complicate congestive heart failure. Management of this disorder requires a balance of both careful medical intervention and well-timed renal revascularization.

Some degree of renovascular disease is remarkably common. Community-based studies indicate that renal artery stenosis is more prevalent with advancing age; in one study, 6.8% of a general population older than 65 years of age had renal artery lesions of more than 60% occlusion (1). When aortography of the renal arteries is performed during coronary angiography, 18% to 24% of patients with coronary disease have at least moderate renal artery stenosis (>50% lumen occlusion) (2, 3). More than 40% of patients who undergo aortography for aortoiliac disease have this disorder. Many of these lesions are identified “incidentally” and may pose minimal, if any, hemodynamic hazard.

Clinicians face complex choices when considering diagnostic studies to identify and treat renovascular disease. The decision to perform noninvasive “screening” tests rests heavily on the pretest likelihood of disease and, even more important, on the pretest commitment of the clinician to act on positive findings. For these and other reasons, the search for an ideal noninvasive vascular study to identify renal artery stenosis has been daunting.

In this issue, Vasbinder and colleagues (4) present results from the Renal Artery Diagnostic Imaging Study in Hypertension (RADISH), a carefully performed prospective comparison of conventional digital subtraction …