Radiology, Vol 153, 619-623, Copyright © 1984 by Radiological Society of North America
Renal vein renin sampling in essential hypertension using hydralazine and the tourniquet test
AS Gomes, AR Sinaiko, L Tobian, JN Cohn, AG Formanek, DJ Roe and K Amplatz
The results of renal vein renin sampling were assessed in 40 patients who
had uncomplicated essential hypertension. All had normal creatinine
clearance, intravenous pyelography, and arteriography. During sampling,
renin release was stimulated in 29 patients with intravenous hydralazine
and in 11 with the tourniquet blood trapping test. Simultaneous sequential
renal vein samples were drawn over a 30-minute period. Positive renal vein
renin ratios (greater than or equal to 1.5) were seen in 52% of the
hydralazine group at 0 minutes and in 69% post- hydralazine. In the
tourniquet group, 27% had a positive ratio at 0 minutes as compared with
64% post-tourniquets. A significant difference was found in renal vein
plasma renin activity between the two kidneys (p greater than or equal to
.0001). The asymmetry of renal vein renin activity and the large renal vein
renin ratios in these two groups suggest the presence of true differences
in renin secretion. These differences may be due to focal nephrosclerosis.
The therapeutic significance of a positive renal vein renin ratio in the
hypertensive patient should be determined in conjunction with
arteriography.
