ROLE OF CAPTOPRIL RENOGRAPHY IN THE DIAGNOSIS OF RENOVASCULAR HYPERTENSION

Eighty-six hypertensive patients with clinical suspicion of renovascul ar hypertension (RVH) were evaluated by captopril renal scintigraphy ( CRS) and intra-arterial digital subtraction angiography (IADSA) to det ermine the usefulness of CRS in the diagnosis of RVH and to predict th e outcome of revascularization procedures. Technetium 99m-diethylenetr iaminepentaacetic acid (DTPA) renal scintigraphy was performed on 2 co nsecutive days before and after captopril administration, Captopril re nal scintigraphy was considered positive a there were changes in the t ime activity curve according to the criteria specified by the American Society of Hypertension working group. Captopril renal scintigraphy d ata were compared with presence or absence of anatomic renal artery st enosis (RAS). Of 86 hypertensive patients investigated, 45 had RAS. Ao rtoarteritis was the cause of RAS in 40 (89%) patients. Revascularizat ion was done in 25 patients, and response to revascularization was com pared with that of captopril renography. Compared with IADSA, CRS show ed a sensitivity of 82.8% and a specificity of 98.2%. Fourteen patient s had bilateral RAS on IADSA. In these patients, CRS was suggestive of bilateral disease in seven patients, unilateral in four, and negative in three. Comparison of CRS with the results of revascularization sho wed a sensitivity and specificity in detecting curable RAS (RVH) of 95 % and 100%, respectively (positive predictive value, 100%; negative pr edictive value, 85%). In conclusion, we found CRS to be useful in the diagnosis of RVH due to aortoarteritis. (C) 1996 by the National Kidne y Foundation, Inc.