The Role Of Radionuclide Renal Imagings In The Diagnosis Of Renovascular Hypertension

Captopril renography has been accepted as a non-invasive method for evaluation of renovascualr hypertension.But some reports have some discrepancy on the sensitivity and specificity for diagnosing of renovascular hypertension.The aim of this study was to evaluate the clinical value of Captopril renography for diagnosing of renovascular hypertension patients with different etiology.Materials and methodsStudy population215 patients with suspected of renovascualr hypertension between January 1993 and December 2006 were studied.Among them,89 men and 126 women,average age 39.2±17.4 years old.All patients underwent radionuclide renography with captopril intervention.All patients had renal artery angiography within 7 days after radionuclide renography.All the patients are divided into two group according the etiology of renovascular hypertension.Group A include 110 patients with identification of renal artery stenosis in Takayasu's arteritis.Group B include 105 patients with identification of renal artery stenosis in non Takayasu's arteritis.The two group patients who had both captopril renography and renal artery angiography were retrospectively analyzed.ResultsAll these 215 patients had hypertension.Among them,there were 89 male and 126 female with an average age of 39.2±17.4 years old.Renal artery angiography was abnormal in 128 patients,the stenosis was≥50%.70 patients had bilateral renal artery stenosis,58 patients had unilateral renal artery stenosis.The sensitivity,the specificity and accuracy of captopril renography for diagnosing renal artery stenosis to all the 128 patients was 92.2%,92.0%and 92.1%.The sensitivity,the specificity and accuracy of captopril renography for diagnosing renal artery stenosis to all the 430 renal vessels was 84.9%,93.4%and 89.8%.All these 110 patients had hypertension with Takayasu's arteritis.Among them,there were 25 male and 85 female with an average age of 30.2±10.7 years old.Renal artery angiography was abnormal in 77 patients,the stenosis was±50%.40 patients had bilateral renal artery stenosis, 37 patients had unilateral renal artery stenosis.The sensitivity,the specificity and accuracy of captopril renography for diagnosing renal artery stenosis to all the 77 patients was 94.8%,90.9% and 93.6%.The sensitivity,the specificity and accuracy of captopril renography for diagnosing renal artery stenosis to all the 220 renal vessels was 88.9%,91.3%and 90.0%.All these 105 patients had hypertension with non Takayasu's arteritis.Among them,there were 64 male and 41 female with an average age of 48.7±18.1 years old.Renal artery angiography was abnormal in 77 patients,the stenosis was≥50%.33 patients had bilateral renal artery stenosis,18 patients had unilateral renal artery stenosis.The sensitivity,the specificity and accuracy of captopril renography for diagnosing renal artery stenosis to all the 51 patients was 88.2%,92.6%and 90.5%.The sensitivity,the specificity and accuracy of captopril renography for diagnosing renal artery stenosis to all the 210 renal vessels was 78.3%,95.0%and 89.5%.ConclusionsCaptopril renography has a definite sensitivity and specificity for diagnosing of renovascular hypertension.Captopril renography has a very higher sensitivity and accuracy in diagnosing of RVH in the patients with Takayasu's arteritis than in those with other etiology.