Pre- and postoperative studies in 72 hypertensive patients with renal artery stenosis, with special reference to renin activity and aldosterone.

Seventy-two patients, aged 6-69 years, were operated on because of presumed renovascular hypertension and subjected to follow-up studies for 4-60 months (mean 28). Unilateral renal artery stenosis was present in 47 patients. Surgery was followed by normalization of blood pressure (BP) in 28 and improvement in 7, whereas 12 showed no response. Sixteen were below the age of 40 and only one failed to respond to surgery. Peripheral venous plasma renin activity (PRA) was increased in 32 and urinary aldosterone elevated in 22 of 35 patients responding favourably to surgery. Renal vein PRA was higher from the kidney with the stenotic renal artery as compared to the contralateral side in all patients responding to surgery. Preoperative peripheral PRA difference was also found in 7 of 12 patients not responding to surgery. Preoperative peripheral PRA was increased in 26 of the patients becoming normotensive after surgery. In 20 of these patients normalization of BP was associated with a fall in peripheral PR. Twenty-five patients had bilateral renal artery stenosis. Four of them had severe hypertension, renal insufficiency and generalized atherosclerosis. They died in immediate connection with operation. Unilateral operation, performed in 11 of the remaining 21 patients, was followed by normalization of BP in 3 and no response in 8. Bilateral reconstructive surgery, performed in 10 patients, resulted in normotension in 2 and improvement in 7. Our studies indicate that determination of peripheral PRA and/or urinary aldosterone can serve as a useful prognostic indicator after surgery in hypertensive patients with renal artery stenosis.