Renal artery stenosis is a narrowing of one or both arteries that supply the kidneys, which switches on the renin-angiotensin system and raises blood pressure. In older adults it is usually caused by atherosclerosis, while in young women it is often fibromuscular dysplasia.
Key symptoms
- Often no symptoms other than high blood pressure
- Blood pressure that stays high on 3 or more drugs
- High blood pressure starting before age 30 or after 55
- Sudden shortness of breath from flash pulmonary edema
What you find on exam
- Very high blood pressure
- Abdominal bruit near the kidneys
- Signs of vascular disease elsewhere: carotid bruit, weak leg pulses
- Hypertensive changes in the eyes
Tests
- Creatinine and potassium; a creatinine rise over 30% after starting an ACE inhibitor or ARB is a clue
- Renal artery duplex ultrasound
- CT or MR angiography
- Unequal kidney size on ultrasound
Treatment basics
- Atherosclerotic disease: blood pressure drugs, a statin, aspirin and smoking cessation
- ACE inhibitor or ARB with close checks of creatinine and potassium
- Fibromuscular dysplasia: angioplasty, often curative
- Stenting for selected patients with flash pulmonary edema or failing medical therapy
Red flags
- Flash pulmonary edema
- Sharp rise in creatinine after starting an ACE inhibitor or ARB
- Hypertensive emergency with organ damage
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Sources: NCCPA PANCE Content Blueprint; NBOME COMLEX-USA clinical presentations; AHA Scientific Statement, Measurement of Blood Pressure in Humans (Hypertension, 2019). Written by Making Synapses. Making Synapses is not affiliated with these organizations.