Renal Artery Stenosis

Question 1

What is the likely cause of renal artery stenosis in these groups?

1. <30 years old
2. > 55 years old

Answer 1

1. Fibromuscular dysplasia

2. Atherosclerotic disease

Question 2

What is the underlying aetiology of renovascular hypertension?

Answer 2

High levels of renin and Ang II produced by an under-perfused kidney supplied by a stenosed artery.

Question 3

Why might starting someone with renal artery stenosis on ACEi/ARBs lead to AKI?

Answer 3

Glomerular filtration relies on high levels of Ang II constricting the efferent.

Question 4

What are the key risk factors in renal artery stenosis?

Answer 4

Smoking, dyslipidaemia, diabetes mellitus.

Question 5

What is this a presentation of?
History of accelerated, malignant, hard to control HTN. Unexplained kidney dysfunction. Multi-vessel coronary artery/peripheral vascular disease. Sudden/unexplained recurrent pulmonary oedema.

Answer 5

Renal artery stenosis

Question 6

How is suspected renal artery stenosis investigated?

Answer 6

1. BP - HTN
2. Abdominal bruit
3. High creatinine, low eGFR
4. Low-normal K+ due to activation of RAAS
5. ARR to exclude primary hyperaldosteronism
6. Rise in creatinine after started on ACEi/ARB should trigger referral.
7. Renal USS, proceed to CTA/MRA if equivocal.

Question 7

What is the management of renal artery stenosis?

Answer 7

1. Aspirin
2. 80mg atorvastatin
3. Low salt diet, smoking cessation, weight reduction, optimise glucose
4. Renal artery angioplasty 1st line in fibromuscular dysplasia (reserve for those with atherosclerosis resistant to medical therapy).

Question 8

What medications are contraindicated in renal artery stenosis?

Answer 8

ACEi/ARB