Renal Artery Angioplasty Periprocedural Care

Updated: Jun 20, 2016
  • Author: Vibhuti N Singh, MD, MPH, FACC, FSCAI; Chief Editor: Kyung J Cho, MD, FACR, FSIR  more...
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Periprocedural Care

Preprocedural Planning

Renovascular disease is present in 10-40% of patients with end-stage renal disease (ESRD); these constitute the fastest-growing group of patients with ESRD. Nonselective correction of renal artery stenosis (RAS) has led to disappointing results. Most groups that compared conservative treatment with angioplasty found only modest or no beneficial effects of angioplasty on renal function and blood pressure (BP).

The CORAL (Cardiovascular Outcomes in Renal Artery Lesions) trial included 947 participants who had atherosclerotic RAS (ARAS) and either (a) systolic hypertension while on two or more antihypertensive drugs or (b) chronic kidney disease; the participants were randomly assigned to medical therapy plus renal artery stenting or medical therapy alone. [36, 14] The investigators did not find stenting to provide significant added benefit with regard to preventing clinical events in this setting.

Patients with a high likelihood of a favorable response should be identified. [15] Factors that affect outcome include the following:

  • Severity of RAS
  • Procedure used to treat RAS (eg, antihypertensive drugs, angioplasty with or without stents, surgery)
  • Nephrotoxicity to radiologic contrast materials
  • Atheroembolism [37]
  • Underlying renal disease forestalling a favorable response in renal function or BP, even after the successful correction of RAS (most important)

Renal resistance may be evaluated by using Doppler ultrasonography or captopril scintigraphy to determine whether patients may or may not respond to intervention. Each factor must be considered before the correction of RAS to achieve satisfactory results in improving renal function and BP.

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Preprocedural Evaluation

Diagnostic studies for renovascular disease include the following:

  • Rapid-sequence intravenous pyelography (IVP) - This test has a sensitivity of 74.5% and a specificity of 86.2%, but limited sensitivity for bilateral or branch RAS; the false-positive rate of 12% in patients with essential hypertension (HTN) [38]
  • Test of the renin ratio in the renal vein - This test has a sensitivity of 80% and a specificity of 62%; use of sodium depletion, hydralazine, nifedipine, and captopril may enhance asymmetric response and increase sensitivity without affecting specificity; renal cysts, pyelonephritis, and ureteral obstruction may increase the asymmetry of renin secretion [39]
  • Radionuclide imaging - This test has a sensitivity and specificity of approximately 95% with use of captopril; addition of furosemide may increase sensitivity; severe renal insufficiency and the presence of bilateral RAS reduce its accuracy [40]
  • Renal artery duplex ultrasonography (RADUS) - This test has a sensitivity of approximately 98% (as compared with arteriography) and a specificity of 98%, as well as a positive predictive value of 99% and a negative predictive value of 97% [41] ; drawbacks are that it is technician-dependent, that it is not universally available, and that as many as 10% of patients cannot be imaged because of body habitus
  • MRA (magnetic resonance angiography) - This is likely to be the test of choice, with a sensitivity of nearly 100% and a specificity of nearly 90% [42] ; drawbacks are that it is nonportable and that it cannot be used in patients with implanted devices, metal artifacts, or claustrophobia or in patients of certain size and weight
  • Spiral (multisection) computed tomography (CT) - Sensitivity and specificity are not yet determined
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