Stroke

Basic Facts

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Renovascular conditions are disorders or diseases affecting the blood vessels of the kidneys.
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Typically, renovascular conditions involve either narrowing of the kidney arteries or blockage of the kidney veins.
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Atherosclerosis, the accumulation of cholesterol and other fats along the lining of artery walls, is a main contributor to renal artery conditions.

The kidneys, two small bean-shaped organs, are located on both sides the spine, below the ribcage. Normal blood flow through the kidneys allows them to excrete wastes, concentrate urine, and conserve electrolytes (mineral salts).

Renovascular conditions include:

  • Renal artery stenosis: Narrowing of the artery that supplies the kidney;
  • Renal vein thrombosis: A blood clot in the vein that drains the kidney;
  • Arterial nephrosclerosis: Inflammation and cell death in the renal arteries; and
  • Scleroderma renal disease: A complication of a skin disorder that causes lesions to develop in the arteries.

Renovascular conditions can cause hypertension (high blood pressure) or eventually renal failure.

WHAT ARE THE SYMPTOMS OF RENOVASCULAR CONDITIONS?

Most renovascular conditions are progressive, meaning that they develop over time. Therefore, they may not cause symptoms initially.

Occasionally a narrowed artery will completely block off, suddenly causing symptoms including:

  • Pain on the sides of the abdomen, legs, or thighs;
  • Blood in the urine;
  • Fever, nausea, and vomiting; and/or
  • Hypertension.

CAUSES AND RISK FACTORS

Most renovascular diseases result from atherosclerosis, the accumulation of cholesterol and other fats on the lining of artery walls. Other causes include:

  • Trauma;
  • The growth of fibrous tissue in the wall of the renal artery;
  • A tumor that blocks the renal blood vessels;
  • Hypertension; and/or
  • Severe dehydration (in children and infants).

Risk factors for renovascular conditions include:

  • Being male and older than 60;
  • Smoking;
  • Obesity;
  • High blood levels of cholesterol or other lipids (fats);
  • Previously episodes of blood clots; and/or
  • A family member with cardiovascular disease.

DIAGNOSIS

To diagnose renovascular conditions, a physician may order a variety of tests to show the renal blood vessels. These tests include:

  • Blood and urine tests
  • Doppler ultrasound
  • Computerized tomography (CT) scan
  • Magnetic resonance imaging (MRI)
  • Magnetic resonance angiography (MRA)
  • Venacavography (A contrast agent is injected into the veins and an x ray is taken.)
  • Renal arteriography (Similar to venacavography, but provides images of arteries, not veins.)
  • Radionuclide scanning (A radioactive substance injected into a patient’s bloodstream emits gamma rays, similar to x rays. A gamma camera collects these rays to assess blood flow through the kidneys.)

TREATMENT APPROACH

Treatments for renovascular conditions depend on the diagnosis. They may include:

  • Medications that prevent clotting (anticoagulants) or medications that dissolve clots;
  • Blood pressure medications (antihypertensives);
  • Angioplasty to widen or unblock arteries; or
  • Bypass surgery.

LIFESTYLE

Stopping smoking, losing weight, and exercising can help slow the progression of renovascular conditions. The physician may also advise eating a diet low in saturated fat to reduce high blood cholesterol, a risk factor for atherosclerosis.