NONINVASIVE DIAGNOSIS OF RENOVASCULAR DISEASE

Objective: To present the epidemiologic and clinical features of renovascular disease and discuss various diagnostic approaches. Design: We describe the findings in patients with fibromuscular dysplasia or atherosclerotic disease of the renal arteries and review pertinent studies from the literature. Results: Renovascular disease is an important cause of resistant hypertension and progressive renal insufficiency, particularly in the elderly population. Improved blood pressure control and renal function after revascularization have generated intense interest in identifying those patients likely to benefit from this intervention. Fibromuscular dysplasia and atherosclerotic renal artery stenosis account for most cases of renovascular disease. Both entities produce resistant hypertension; the latter is the more common cause of progressive renal insufficiency-occasionally leading to end-stage renal disease. Angiotensin-converting enzyme inhibitor-related renal dysfunction, otherwise unexplained renal insufficiency, and recurrent pulmonary edema are increasingly recognized clinical manifestations of renovascular disease. Traditional screening tests such as intravenous pyelography, intravenous digital subtraction angiography, radionuclide scintirenography, and measurement of the peripheral venous plasma renin activity have limited accuracy for diagnosing renal artery stenosis and do not accurately predict the blood pressure response to revascularization. In comparison, recently developed noninvasive tests such as captopril renography, renal artery duplex sonography, and magnetic resonance angiography seem to be more accurate and, in the case of captopril renography, may be more predictive of the blood pressure response to revascularization. Conclusion: Future directions in the area of renovascular disease should include a direct comparison among these new noninvasive diagnostic techniques, with a particular focus on the identification of those patients most likely to benefit from revascularization in terms of both blood pressure control and improved renal function.