Diagnosis and management of renovascular hypertension

The clinical history is seldom helpful in establishing a diagnosis of renovascular hypertension. Symptoms are not different from those accompanying hypertension due to other causes, except for the occasional pain associated with a renovascular accident. Generally, the age and sex of patients reveal a much higher incidence of fibromuscular lesions in young women and of atheromatous lesions in older men. In a surgically treated group of 100 patients with apparent renovascular hypertension, 37 gave a family history of significant hypertension. Long duration of the elevation of blood pressure is so common among patients with renovascular hypertension that we have not been able to use recency to distinguish the cause of hypertension. Physical findings may be distinctly helpful in establishing a diagnosis. If hypertension is of one year's known duration, or longer, and parenchymal renal disease and adrenal causes have been excluded, the physician should strongly suspect renovascular hypertension when examination of the optic fundus reveals severe retinal arteriolar narrowing and focal constriction without significant chronic hypertensive sclerosis. A continuous bruit over the lateral upper region of the abdomen virtually confirms the presence of functionally significant severe renal artery stenosis. Systolic-diastolic bruits of high frequency (pitch), long duration and lateral location should also be considered as strongly suggestive of a renovascular lesion even if screening procedures such as urography or isotope renography reveal no significant differences of renal size or function. The combination of isotope renography and excretory urography can produce comparative estimates of mass and function of the separate kidneys. Neither procedure alone will permit a diagnosis of renal artery stenosis, and therefore the results of each should be considered as normal or abnormal rather than as positive or negative. Severe unilateral renal artery stenosis, or stenosis more severe on one side than the other, is commonly associated with a smaller renal size and renographic abnormality on that side; but these procedures may indicate that the kidneys are of equal size and have equal function even though the patient has surgically remediable hypertension. Despite improvement in screening procedures, renal artery stenosis can be diagnosed only by renal arteriography. The significance of these lesions should be confirmed by differential renal function studies or renal venous