Low-dose captopril scintigraphy in the evaluation of renovascular hypertension.

This study compared the results of renal scintigraphy with simultaneous administration of Tc-99m DTPA and I-131 Hippuran (before and after 25 mg of oral captopril) with the results of the renal arteriogram and renal vein renins (before and after the administration of 25 mg of oral captopril) to evaluate the sensitivity and specificity of renal scintigraphy in the diagnosis of renovascular hypertension. The results of 21 consecutive patients suspected of having renovascular hypertension who underwent scintigraphy and renal arteriography were analyzed. Renal scintigraphy postcaptopril detected all the cases of renovascular hypertension (eight patients) plus two additional patients who had significant renovascular stenosis but no renin overproduction. The results indicate that the renal scintigram, before and after the administration of captopril, is an accurate and sensitive test for the detection of renovascular hypertension and should be used as a screening procedure before arteriography is considered.