Hypertension Secondary to Renal Artery Occlusive Disease

Abstract

Historically, the awareness of renal artery narrowing as a curable cause of hypertension has evolved gradually, highlighted especially by Goldblatt and Poutasse. The increasing use of renal arteriography over the past 8 years in this hospital has yielded a total of 70 patients with renal artery abnormalities out of 110 hypertensive patients examined. In order to select the hypertensive patients most likely to have demonstrable arterial lesions, certain indications for arteriography were used. Most useful among these were the presence of an epigastric bruit, malignant hypertension, atheroselerosis of the abdominal aorta, and recent onset of hypertension. However, no one indication was always present in patients with lesions or always absent in those without abnormalities. Of the 70 patients with renal artery abnormalities, 54 were considered to represent sufficient renal artery stenosis to be potential candidates for surgical correction, while 16 had minor renal artery abnormalities. Atherosclerotic lesions occurred in 63 per cent of the patients with significant lesions, fibromuscular hyperplasia in 28 per cent, unilateral renal artery hypoplasia or atrophy in 7 per cent, and one case had embolic renal artery occlusion. Fifty-four per cent of all patients with significant lesions had bilateral disease. The patients with atherosclerotic lesions and those with fibromuscular hyperplasia differed markedly in sex distribution, age, and severity of hypertension. It is suggested that the retrograde transfemoral catheterization technic may be associated with fewer complications in patients without extensive occlusive atherosclerotic disease of the aorta, and iliac and femoral arteries. At operation the radiologic findings were confirmed in all but one patient. Corrective surgical procedures were performed in 38 patients, including nephrectomy, endarterectomy, segmental resection with reanastomosis, and splenorenal arterial shunt. Of the 31 patients who survived, 25 (81 per cent) had a postoperative fall in blood pressure, 14 to normal, in addition to improvement in clinical status. The follow-up period, however, is not yet sufficiently long to permit definite conclusions. Seven patients died; most of these had bilateral renal artery disease and extensive atherosclerosis of the cerebral and coronary arteries. Divided renal function studies were of limited diagnostic value because of the high incidence of bilateral lesions. In all patients with significant differences in renal sodium and water excretion, a postoperative fall in blood pressure occurred, but the same number of patients with equal bilateral excretion also had a fall in blood pressure. The importance of suspecting renal artery lesions in hypertensive patients regardless of age, severity of hypertension, or renal function is stressed. The question is discussed whether all patients with sustained hypertension should undergo arteriography. Although further studies to determine the true prevalence of occlusive renal artery lesions in the hypertensive population are in order, the fact that 50 per cent of our 110 patients had occlusive lesions and 60 per cent of the operated cases had a fall in blood pressure attests not only to the prevalence of the lesion but also to its potential curability.