Renal vein renin activity in the prognosis of surgery for renovascular hypertension

Twenty-four hypertensive patients underwent corrective surgery for renal hypertension. The postoperative follow-up period was one year or more in all. In twelve patients the results were classified as excellent (five patients) or good (seven patients). Type of surgery (nephrectomy, thirteen patients; vascular repair, eleven patients) was not a factor in the clinical results. Renal vein renin activity ratio and absolute renal vein renin activity from the involved kidney provided the most accurate means of predicting surgical results. The ratio correctly predicted the surgical result in eleven of fourteen patients, and the absolute level correlated correctly in all but one of fourteen patients. Divided ureteral function tests did not distinguish between patients whose condition was and was not improved by surgery, and the intravenous pyelogram, although adequate for screening for the presence of functional renovascular disease, included a high proportion of false-positive tests. Aortography, although revealing the arterial stenosis in all instances, emphasized the need for confirmation of the functional significance of the lesion since half the patients with stenosis did not respond to surgery. On the basis of our experience, renal vein renin determinations appear to be a highly reliable means of selecting patients for corrective renal surgery.