Renal venous renin sampling. Prospective study of technique and methods.

During a three-year period, 107 patients undergoing renal arteriography were studied to evaluate the influence of renin sampling techniques and contrast material administration on renal venous renin activity. Plasma renin activity was nearly equal in three extrarenal sampling sites (antecubital vein, aorta, and lower inferior vena cava). Values for renal vein renin activity obtained with a single catheter (nonsimultaneous sampling) did not differ significantly from those obtained with two catheters (simultaneous sampling). Similarly, contrast material had no significant effect on renal vein renin activity levels. Thus, in hypertensive patients, sampling for renal venous renin activity can be performed accurately with a single venous catheter after renovascular disease has been demonstrated by arteriography.