Renal Artery Stenosis Flashcards
What is the etiology of most RAS?
Most cases of RAS result from atherosclerotic ischemic renal disease
What age group is ras most prevalent in?
Most common in adults > 45 yrs with atherosclerotic disease
What is a rare cause of ras?
Fibromuscular dysplasia , most commonly seen in young women
What are risk factors of ras?
- Atherosclerotic vessel disease
- Kidney disease
- Diabetes mellitus
- Tobacco use
- HTN
What are the sxs of ras?
- HTN: Unexplained HTN in young woman < 40 yrs should be investigated for RAS
- Moderate to severe retinopathy
- Abdominal bruit on affected side
Bun/Cr test results in ras
Increased
What does a kidney US look like in ras?
May revel asymmetry of kidneys
What other imaging studies are used to screen for ras?
Doppler ultrasonography
CT angiography
Magnetic resonance angiography (MRA)
What is the sensitivity and specificity of doppler us?
> 90% (if experienced sonographer)
What type of pts should not get a doppler us?
Poor choice for obese pts or pts who are unable to lie supine
How does doppler us work?
Measurements of blood flow are made at the aorta and along each third of renal artery in order to assess the disease
What is a misc. advantage of doppler us?
relatively inexpensive
What is the sensitivity of CT angiography?
77-98%
How does a ct angiography work?
Noninvasive procedure
Spiral CT scan with contrast
What is a disadventage of MRA?
expensive
What is the sensitivity of MRA?
77-100%
What is the imaging agent in MRA?
gadolium
Has been asst with nephrogenic fibrosis
What is the gold standard for diagnosing ras?
Renal angiography
Where are lesions most commonly located?
proximal third or ostial region of renal artery
How does fibromuscular dysplasia appear on a renal angiography?
Fibromuscular dysplasia has characteristic “beads on a string” appearance on angiography
What are the medical treatments for ras?
Medical management: BP control DM control Smoking cessation Manage dyslipidemia
What are the surgical options for ras?
Surgical bypass
What are the procedural option for ras?
- Angioplasty with or without stenting
- May reduce number of antihypertensive meds
- Does not significantly change progression of kidney dysfunction compared to pts medically managed
True/false: Angioplasty is less safe than surgery
False.
Angioplasty is equally as effective and safer than surgical revision
