Renal Artery Stenosis

1. High Blood Pressure (Hypertension) Slideshow Pictures
2. Take the Salt Quiz!
3. Lowering Blood Pressure Exercise Tips Slideshow Pictures

• What is renal artery stenosis?
• What are the causes and risk factors for renal artery stenosis?
• What are the signs and symptoms of renal artery stenosis?
• What are the exams and tests for renal artery stenosis?
• What is the treatment for renal artery stenosis?
• What is the follow-up for renal artery stenosis?
• What is the outlook for renal artery stenosis?

• Aside from filtering blood and making urine, the kidneys have other functions. One such function is monitoring blood pressure (performed by special cells called macula densa).
• Using a chemical messenger called angiotensin, these cells can help adjust blood flow throughout the body and maintain normal blood pressure.
• The angiotensin acts by increasing muscle tone in small artery walls to help boost blood pressure. Angiotensin also stimulates the release of aldosterone, which helps the body retain sodium and water, increasing the amount of fluid within the blood vessels.
• Most people with high blood pressure have essential hypertension (hyper=more + tension=pressure), meaning that the cause of the high blood pressure is unknown. However, one known cause of hypertension is renal artery stenosis (renal=kidney + stenosis=narrowing).
• Each kidney gets its blood flow via a renal artery that arises from the aorta, the major blood vessel from the heart.
• If one of the renal arteries narrows, it may cause decreased blood flow to the kidney and to the macula densa (the specialized, blood-pressure sensing cells in the kidney). These cells falsely presume that this low blood flow is being experienced by the rest of the body and that overall blood pressure is too low. They respond by increasing secretion of angiotensin, triggering the body's response to increase blood pressure.

The most common cause of renal artery stenosis is atherosclerosis, the same condition that causes narrowing of the arteries in coronary heart disease and stroke, and the risk factors are the same as well. Cholesterol plaques build up along the walls of the renal artery and gradually cause narrowing. Risk factors for renal artery stenosis include:

• smoking,
• diabetes, and
• high blood pressure.

Other causes of stenosis (narrowing) of the renal artery include:

• fibromuscular dysplasia, an abnormal thickening of the muscles of the artery wall, most often seen in young women
• arteritis or inflammation of the artery
• aneurysm of the artery
• compression of the artery by an outside mass; for example, a tumor

Must Read Articles Related to Renal Artery Stenosis

Acute Kidney Failure Kidney failure, or the ability of the kidneys to filter water and waste, is caused by

• prerenal,
• postrenal, or
• renal problems with the ki...

learn more >>

Chronic Kidney Disease Twenty percent of people over the age of 20 years will develop chronic kidney disease in their lifetime. Chronic learn more >>

Dehydration in Adults Dehydration occurs when the loss of body fluids (mostly water), exceeds the amount that is taken in. Causes of learn more >>

See the Entire Renal Artery Stenosis Topic Guide »