Renal Venous Renin Determinations in the Diagnosis of Surgically Correctable Hypertension

Renin activity in renal vein plasma was measured in six normal subjects and 59 hypertensive patients. The average renin value in renal venous plasma in normal subjects was the same as that found in patients with essential hypertension and renal parenchymal hypertension. Renal venous renin levels were markedly elevated in patients with significant renal lesions who were improved by surgery but were normal in patients with insignificant renal artery stenosis. We defined an abnormal renal vein renin level as one which is higher than 4.1 ng/ml of plasma, the highest normal, and which is also more than twice as great as the level obtained from the opposite kidney. On 19 patients who were operated upon for renal hypertension, there were no "false positive tests," and two "false negative tests." One patient with essential hypertension had abnormal values by these standards. Since occasional "false positive" and "false negative" results occur, we presently recommend that this test be used with, but not to the exclusion of, other tests of renal function in preoperative evaluations. As experience with the test increases, and as more prospective studies are done, it may prove to be the single most useful device to predict surgical success in patients with renal artery and renal parenchymal hypertension.