[Comparison of captopril angioscintigraphy and the renin test in diagnosis of renovascular hypertension].

Captopril renin test (CRT) and captopril angioscintigraphic test (CAT) were simultaneously performed in 130 patients with arterial hypertension (72 women, 58 men, average age 48 years) and suspension for renovascular hypertension (RVH) in initial renal angioscintigraphy. 16 positive CAT results and 26 positive CRT results according to Muller qualification as well as 31 positive results according to Frederickson qualification were obtained. In 32 patients the suspension of RVH was formed on the basis of clinical features of accelerated phase of hypertension. In 42 patients the renal arteriography was performed-this group includes all patients with positive results of at least one captopril test, among them 32 patients with clinical symptoms of accelerated hypertension. In 24 cases the critical stenosis of renal artery was revealed. The diagnostic value of CRT-M, CRT-F and CAT was referred to critical stenosis of renal artery (> 75% of the lumen) as a criterium of RVH. The following values of sensitivity, specificity and discrimination capacity for CRT were established: for CRT-M 70%, 50%, 21% respectively, for CRT-F 88%, 44%, 40% respectively. CAT demonstrated the highest specificity (100%) as well as discrimination capacity (75%) in spite of the relatively low sensitivity (67%). The absence of false positive results of CAT as well as considerable percentage of false positive CRT results stress the importance of isotopic test as basic method for the diagnosis of RVH. Simplicity of the test, its low price and availability as well as immediately obtained results allow to propose CAT as a routine ambulatory screening test for RVH.