Prospective analysis of strategies for diagnosing renovascular hypertension.

Abstract

Renovascular hypertension is a potentially curable form of high blood pressure. However, it is unclear how best to select patients who are likely to have renovascular hypertension, what diagnostic strategy to use in these selected patients, and how to predict the hemodynamic significance of a renal artery stenosis. We determined the prevalence of renovascular hypertension in adults who exhibited suggestive clinical features. In these clinically selected patients, we then determined the test characteristics of various diagnostic and potential screening tests. Renovascular hypertension was diagnosed if correction of renal artery stenosis resulted in decreased blood pressure. Of the 66 hypertensive adults evaluated, 11 (16.7%) had renovascular hypertension. Captopril-stimulated peripheral renln activity detected renovascular hypertension with 73% sensitivity, 72% specificity, 38% positive predictive value, and 92% negative predictive value. Less optimal combinations of sensitivity and specificity were found for differential glomerular filtration rate renography, differential effective renal plasma flow renography, and selective renal vein renin ratios, each performed after a single dose of captopril. Intravenous digital subtraction renal angktgraphy detected all patients with renovascular hypertension and was normal in 71% of patients with essential hypertension. To evaluate potential screening tests for renovascular hypertension, we calculated predictive values applied to a low prevalence population. If the observed sensitivities and specificities apply to a population with 5% prevalence of renovascular hypertension, captopril-stimulated peripheral renin would have a positive predictive value of 12% and a negative predictive value of 98%. In 16 patients with known renal artery stenosis, neither the captopril-stimulated renal vein renin ratio nor captopril-stimulated differential renography accurately predicted blood pressure response to correction of the stenosis. We conclude that clinical criteria can identify a subgroup with 16.7% prevalence of renovascular hypertension. In this high prevalence group, intravenous digital subtraction renal angiography will identify virtually all patients with renovascular hypertension, and a normal study will be sufficient to exclude renovascular hypertension. In unselected hypertensive patients, screening with captopril-stimulated peripheral renin activity may be the most useful and efficient procedure for identification of patients with renovascular hypertension. Functional tests do not accurately predict the hemodynamic significance of a renal artery stenosis. {Hypertension 1989;14:247-257) R enovascular hypertension (RVH) is a potentially curable form of high blood pressure. Its treatment, with angioplasty or surgery, provides the opportunity to prevent cardiovascular morbidity and mortality due to hypertension and to avoid the expense and potential morbidity of lifelong pharmacotherapy for hypertension. Therefore, this condition should be identified and treated whenever poss...

Simplified captopril renography in diagnosis and treatment of renal artery stenosis.

“…We used clinical criteria similar to those employed by Svetkey and associates 7 in their prospective study of diagnostic methods for renal artery disease. This group identified a population with a lower prevalence of structural renal artery lesions (24%) than we found, perhaps because they used age alone as a criterion (all hypertensives less than 25 or more than 45 years of age at first presentation were considered eligible) and excluded those patients with a serum creatinine concentration of greater than 2.0 mg/dl and those with recent coronary or cerebrovascular events.…”

“…We did not exclude any patient who could tolerate the study and did not evaluate patients simply on the basis of age at the initial diagnosis of hypertension. In addition, unlike Svetkey and associates, 7 we considered patients with atherosclerotic disease in other vascular beds to be at high risk for renal artery stenosis. 37 Using our criteria, we found a population with a 47% prevalence of renal artery stenosis.…”

Similar prevalence of renovascular hypertension in selected blacks and whites.

“…(Captopril-stimulated selective renal vein renin was measured, as previously reported, 7 but the results of these and peripheral renin measurements were not known until after interventional treatment had occurred.) Subjects without significant renal artery stenosis on arteriography were treated with antihypertensive medication.…”

Urinary prostaglandin and prostaglandin metabolite excretion in patients with essential hypertension or hypertension with renal artery stenosis

“…Because renovascular hypertension can be treated successfully in a large number of patients, it is worthwhile to try to identify those with this condition among the general hypertensive population [22][23][24][25]. However, the certain diagnosis of a renal artery stenosis can only be made by an-giography [22][23][24][25].…”

“…However, the certain diagnosis of a renal artery stenosis can only be made by an-giography [22][23][24][25]. In view of the low prevalence of renal artery stenosis in the hypertensive population, angiography, because of its invasive nature and cost, cannot be used as a screening procedure.…”