Renal Artery Stenosis Diagnosis

According to the National Kidney and Urological Disease Information Clearinghouse (NKUDIC), renal artery stenosis (RAS) occurs when one or both arteries that carry blood to the two kidneys becomes constricted. Renal refers to kidney and stenosis defines the narrowing. Renal artery stenosis impairs kidney function and leads to high blood pressure. There are several treatment methods available for RAS patients, but the condition may return.

• Urinary system

Risk Factors

• The University of Maryland Medical Center (UMMC) says people who smoke are more likely to develop renal artery stenosis as are individuals who are overweight. RAS is most often diagnosed in people over age 50. Men are more prone to the disease than are women. Additional risk factors include diabetes, high cholesterol and a family history of heart disease.

Causes

• Nearly all cases of renal artery stenosis are due to a hardening of the kidney arteries (atherosclerosis). A buildup of plaque (fat, cholesterol, calcium and other substances) causes the artery wall to solidify and narrow. This restriction inhibits the flow of the blood supply and can harm the kidney, making it less able to eliminate excess fluid from the blood.

  Some cases of renal artery stenosis such as fibromuscular dysplasia may be due to an abnormal growth of the cells in the walls of kidney arteries.

Diagnosis

• Renal artery stenosis isn't likely to cause any signs or symptoms until it has advanced. When RAS becomes severe it may result in high blood pressure. Your doctor will perform a physical exam and may conduct certain diagnostic tests.

  Your doctor may order an ultrasound (sound waves to create images of an internal organ) to get a look at the artery. An angiogram (uses dye to look inside blood vessels by inserting a thin flexible tube into the artery) is another diagnostic tool that creates a better image than an ultrasound.

Medications

• Treatment for renal artery stenosis will include medications (beta blockers, diuretics) to lower high blood pressure caused by the disease.

  Your doctor also may prescribe a cholesterol-lowering drug (Statins such as atorvastatin/Lipitor, simvastatin/Zocor) to prevent the plaques from forming in the arteries, as well as a blood thinner (aspirin) to improve blood flow through the arteries.

Surgery

• In severe cases of renal artery stenosis surgeries such as an endarterectomy (clearing plaque from the artery) or a bypass (a vein or synthetic tube is used to create an alternate path for blood to move around the blocked artery into the kidney) may be performed.

  It's important to stay in close contact with your doctor following a surgical procedure because there is always a chance of recurrence.