Natural History of Renal Arterial Disease

Information about the natural history of renal arterial disease is important for the approach to a precise selection of hypertensive patients for medical or surgical therapy. Surgery carries a high risk of myocardial infarction and stroke in patients with renal atherosclerosis and associated coronary and cerebrovascular disease. Moreover, technical problems arise when the arterial disease affects branches of the renal artery, is bilateral, or affects the renal artery supplying a solitary kidney. Although antihypertensive drug therapy has proved effective in controlling blood pressure in patients with renal vascular hypertension (1), concern may arise that renal function deteriorate because of progression of the arterial disease. This report presents the information obtained in 91 patients studied by serial renal arteriography for periods ranging from six months to ten years. Clinical Material, Method, and Criteria of Study The 91 patients (32 males and 59 females) in the study were admitted to the Cleveland Clinic Hospital for diagnosis of the cause uses of hypertension. Their ages ranged from nine to sixty-four years, with a mean of fifty years (Table I). Except for one patient, all had occlusive renal arterial disease at the time of the initial examination. These patients had not been operated upon for any of the following reasons: (a) contraindications because of previous medical complications of atherosclerosis (myocardial infarction, stroke) and other medical diseases; (b) extensive renal arterial disease that precluded reconstructive arterial procedures; (c) mildness of hypertension or occlusive disease; (d) evidentiary doubt as to the relationship of the observed stenosis to the hypertension. Included also in the series were 17 patients who had been operated on for renal arterial disease but with residual disease either on the operated side or in the contralateral kidney. The diagnosis of the type of renal arterial disease was made from arteriographic features based upon the pathologic-arteriographic correlation of McCormack and his associates (2, 3). The disease was first categorized as atherosclerotic or nonatherosclerotic. The nonatherosclerotic lesions were divided into four types according to the composition and location of disease in the arterial wall. These types are : medial fibroplasia with aneurysms, subadventitial fibroplasia, intimal fibroplasia, and fibromuscular hyperplasia. Since with continuing experience there has been considerable difficulty in arteriographic differentiation between intimal fibroplasia and fibromuscular hyperplasia, these types of renal artery disease have been grouped together. In 23 patients, accuracy of the arteriographic diagnosis was confirmed by examination of renal arterial tissue. The number and intervals of progress examinations are given in detail in Tables II and III. The intervals between the initial and the last examinations ranged from six months to ten years.