Renal Artery Stenosis
Renal artery stenosis (RAS) is the narrowing of one or both of the renal arteries, the blood vessels that carry blood to the kidneys from the aorta. RAS often causes high blood pressure and reduced kidney function, but many times it has no symptoms until it becomes severe. Most cases of RAS are caused by a condition called atherosclerosis, which leads to narrowing and hardening of the renal arteries. RAS develops when plaque builds up on the inner wall of the renal arteries, causing them to harden and narrow.
RAS also can be caused by fibromuscular dysplasia, an abnormal growth of tissue within the wall of the artery, which also causes the blood vessels to narrow.
Symptoms of Renal Artery Stenosis
People with RAS may develop the following symptoms:
- High blood pressure
- Headaches
- Fatigue
- Shortnes of breath
- Edema (swelling) of the hands or feet
- Muscle cramps
- Nausea
- Weight loss
- Numbness
Diagnosis of Renal Artery Stenosis
The diagnosis of RAS starts with a complete review of systems and physical examination. Blood and urine tests may be performed to check cholesterol and evaluate kidney function. Additional diagnostic tests may include the following:
- Ultrasound
- CT scan
- Magnetic resonance arteriogram (MRA)
- Angiogram
Treatment of Renal Artery Stenosis
RAS may initially be treated with conservative methods designed to lower blood pressure and reduce the risk of further narrowing of the renal arteries. These methods may include stopping smoking, eating a healthy diet, and exercising. Medication to lower cholesterol and control blood pressure may also be prescribed. If conservative methods are not effective, renal artery angioplasty and stenting may be indicated.