Screening for renovascular hypertension. Is renal digital-subtraction angiography the preferred noninvasive test?

Screening for renovascular hypertension. A which hunt.

“…Calculations of sensitivity were based on no more than 11 patients. The 100% sensitivity reported for digital subtraction angiography is at variance with the 7-25% incidence of uninterpretable studies reported elsewhere, 12 in part because equivocal studies were considered abnormal. Another approach would be to consider such intermediate results as a separate category, calculating their likelihood among patients with and without RVH.…”

Renovascular Hypertension

“…The suspicion of renovascular disease is substantiated by the finding of 1) fractional share of total renal function for one kidney within one to three min after injection less than 43 per cent, or 2) time to peak more than 3.5 min at one or both sides and the ratio between the peaks outside normal limits (0.85-1.15), or 3) residual activity 20 min after injection higher than 22 per cent at one or both sides and the ratio between the residual activities not within 0.64 to 1.34 (24). The nosographic sensitivity of the 13II-hippuran renogram does not differ from that of the rapid-sequence urography (mean: 74 per cent, range: 69-97 per cent in 8 studies including 934 angiography-controlled patients) (29). Refinement as performing the examination during dehydration has not improved the reliability of the method (50).…”

“…With a false-negative rate ranging from 7 to 58 per cent (29,39,46,79) with an average of 26 per cent (29) in 19 studies including 2040 angiography-controlled patients, the procedure is now regarded as unacceptable as a screening modality for renovascular disease. means of selecting patients most likely to benefit from testing (and subsequent surgical or angioplastic treatment) is necessary (42).…”

Diagnostic imaging of renal artery stenosis

“…55 Studies have shown that good results can be obtained using intra-venous DSA for the diagnosis of RAS with sensitivities and specificities of 88-100% and 90-93% respectively. 56,57 However, it cannot achieve equivalent resolution to conventional angiography and may miss up to 50% of cases of fibromuscular dysplasia and stenoses in small branch arteries. 58 In addition a larger volume of contrast is needed for each series of images increasing the risk of congestive cardiac failure and nephrotoxicity in patients with pre-existing renal impairment.…”