Renovascular hypertension. Relationship of surgical curability to renin-angiotensin activity.

Fifteen patients whose renovascular hypertension was cured or improved by renal artery reconstructive surgery or nephrectomy (or both) underwent studies of their renin-angiotensin systems preoperatively. These studies included measurements of peripheral venous renin activity in the erect position without diuretic preparation, blood pressure response to blockade of endogenous angiotensin II with a saralasin infusion in the acutely sodium-depleted state, and levels of renal venous renin activity, also after sodium depletion. In 13 of these 15 patients who had benefitted from surgical intervention for relief of renovascular hypertension, at least one index of renin dependency was positive. Two patients had negative results in all of the tests. On the basis of these findings, we concluded that cure or improvement of renovascular hypertension is possible even though these three parameters of renin-angiotensin overactivity are negative.