Renal Artery Stenosis

Renal artery stenosis occurs when an artery in the kidney narrows. This causes a decrease in blood flow to that kidney. The kidneys are a pair of bean-shaped organs. They filter and remove waste from the blood. Stenosis is narrowing that restricts an opening. Each kidney regulates the body’s blood pressure to make sure that each organ has enough oxygenated blood. This happens by activating the renin-angiotensin hormone system. Renal artery stenosis triggers the release of these hormones. This release causes hypertension, which is also known as high blood pressure.

  • Causes

    There are several diseases of arteries that can cause them to become narrowed, including:

    • Atherosclerosis—the most common
    • Fibromuscular dysplasia

  • Definition

    Renal artery stenosis occurs when an artery in the kidney narrows. This causes a decrease in blood flow to that kidney. The kidneys are a pair of bean-shaped organs. They filter and remove waste from the blood. Stenosis is narrowing that restricts an opening.

    The Kidney and Its Main Blood Vessels
    IMAGE

    Copyright © Nucleus Medical Media, Inc.

    Each kidney regulates the body’s blood pressure to make sure that each organ has enough oxygenated blood. This happens by activating the renin-angiotensin hormone system.


    Renal artery stenosis triggers the release of these hormones. This release causes
    hypertension, which is also known as high blood pressure.

  • Diagnosis

    Your doctor will ask about your symptoms and medical history. A physical exam will be done. If you have elevated blood pressure, a search for its cause can involve many different tests. Unless there is a specific reason to suspect renal artery stenosis, it may not be considered at first.

    Your bodily fluids may be tested. This can be done with:

    • Repeat blood pressure measurements
    • Blood tests
    • Urine tests

    Images may be taken of your kidneys. This can be done with:

    • X-rays
      with contrasting dye
    • X-rays with contrast injected directly into the renal arteries
    • Ultrasound
    • Radioisotope imaging
    • CT
      or
      MRI
      scans with or without injected contrast agents


    Your heart's activity may be measured. This can be done with an
    electrocardiogram.

  • Prevention

    Renal artery stenosis is an unusual cause of hypertension, but an important one because it is curable.
    The best way to detect hypertension is to have routine blood pressure measurements.

    You can also prevent atherosclerosis by exercising regularly, eating a heart healthy diet, quitting smoking, and drinking less alcohol.

  • Risk Factors

    Factors that increase your risk of developing renal artery stenosis include:

    • Sex: male
    • Age: over 50
    • Atherosclerosis elsewhere in your body
    • Previous stroke or heart attack
    • Smoking
    • Hypertension
    • Diabetes
    • Cholesterol and triglyceride disorders

  • Symptoms

    Most patients with renal artery stenosis have no symptoms. However, it may also cause:

    • Fluid retention
    • Shortness of breath
    • Headaches
    • Ankle swelling

    If both renal arteries are blocked, kidney failure occurs.

  • Treatment

    Talk with your doctor about the best treatment plan for you. If there is significant stenosis and you are healthy, repairing the renal artery may be considered before medical treatment. Treatment options include: