Renal Artery Stenosis
Different from renal artery stenosis in that it is bilateral and more gradual
What our notes say
- Different from renal artery stenosis in that it is bilateral and more gradual (Renal Vascular Diseases: Nephrosclerosis & Renal Artery Stenosis)
- Reduced renal perfusion: hepatorenal syndrome, NSAIDs and ACE inhibitors or ARBs, renal artery stenosis. (Junior Clerkship in Internal Medicine (MBIM4100) main exam, Paper One: 31 Januar)
- | Renal artery stenosis | Abdominal bruit, flash pulmonary oedema, creatinine rise on ACE inhibitor; Doppler or CT angiography | (Hypertension)
- | Renal Artery Stenosis | 2–5% of HTN, surgically curable; 70% atheroma (older men) vs fibromuscular dysplasia (younger women); ↑renin → angiotensin II → HTN | (Exam Prep: Skin Infections, Psoriasis & Pemphigus)
- | Vascular | Nephrosclerosis, Renal artery stenosis, TMA (HUS/TTP) | HTN↔nephrosclerosis cycle; Shiga toxin=HUS; ADAMTS13=TTP | (Exam Prep: Skin Infections, Psoriasis & Pemphigus)
- Renal artery stenosis = curable cause of hypertension; fix the narrowing, fix the BP (Renal Vascular Diseases: Nephrosclerosis & Renal Artery Stenosis)
Study material on Renal Artery Stenosis
Practice questions on Renal Artery Stenosis
Renal artery stenosis causes hypertension primarily through which mechanism?
- Increased sympathetic nervous system activity directly affecting vascular tone
- Activation of the renin-angiotensin-aldosterone system (RAAS) due to reduced renal perfusion
- Reduced glomerular filtration rate leading to volume overload
- Endothelial dysfunction and impaired nitric oxide production
Answer: B. Renal artery stenosis reduces blood flow to the juxtaglomerular apparatus, which stimulates renin release, activating the RAAS and causing hypertension. This is secondary hypertension. ---
The most appropriate initial diagnostic test for suspected renal artery stenosis (RAS) is
- Renal biopsy
- Angiography (gold standard, but invasive)
- CT angiography or MR angiography (MRA)
- Renal ultrasound with Doppler (often first line, non-invasive screening)
Answer: D. Renal ultrasound with Doppler is a common first-line screening test due to its non-invasiveness, though its sensitivity/specificity are operator-dependent. CT angiography and MR angiography are more definitive non-invasive tests. Angiography is the gold standard but invasive. RAS should be suspected in sudden onset or refractory hypertension, especially with unexplained AKI after starting ACEi/ARB, or asymmetric kidn