What is renovascular hypertension?

Renovascular hypertension is high blood pressure due to disease of the kidneys.

What is the cause?

The most common cause of poor blood flow to the kidneys is narrowing of the arteries that carry blood. This narrowing can be caused by several things, including high levels of blood fats (called cholesterol), smoking, diabetes, age, heavy alcohol use and using cocaine. The most common of these is high cholesterol, when fatty deposits called plaque may build up in blood vessels and make them narrower. When arteries to the kidneys narrow and harden, they block the flow of blood. When less blood reaches the kidneys, they respond as if you have low blood pressure. The kidneys release a hormone that raises your blood pressure.

Fibromuscular dysplasia is a disease that causes extra tissue to grow in the walls of the kidney arteries. This makes the walls thick and narrows the arteries.

Tumors around the kidney or injuries that put pressure on the kidney arteries also may reduce blood flow.

What are the symptoms?

High blood pressure usually does not cause symptoms. Your provider may suspect renovascular hypertension if you:

• Suddenly start having high blood pressure before you are 30 or after age 55
• Have high blood pressure that gets worse while you are taking blood pressure medicine
• Have high blood pressure and blood tests show that your kidneys don’t work as well as they should.

Symptoms of very high blood pressure may include:

• Headache or confusion
• Blurry or double vision
• Nosebleeds
• Nausea or vomiting

How is it diagnosed?

Your healthcare provider will ask about your symptoms and medical history and examine you. Tests may include:

• Blood tests
• An ultrasound, which uses sound waves to show pictures of the kidneys and the arteries to the kidneys
• Renogram, which uses a small amount of radioactive material injected into your blood to make detailed pictures of your kidneys
• Magnetic resonance arteriography, which uses a strong magnetic field and radio waves to show detailed pictures of the arteries around the kidney
• Renal arteriogram, which is a series of X-rays taken after your healthcare provider injects a special dye into the blood vessels around the kidney

How is it treated?

Your provider will prescribe medicine to lower your blood pressure. If your arteries are blocked, you may need a procedure to increase blood flow to your kidneys:

• A balloon angioplasty opens blocked blood vessels. A metal mesh device called a stent may be left in the blood vessels to help keep them open.
• You may need surgery to remove the blockage in the artery.
• Bypass surgery uses blood vessels from other parts of your body, or manmade material, to make a new path around a blocked area.

You may need to take blood pressure medicine for the rest of your life, even if you have surgery. If high blood pressure is not treated, it often leads to serious problems, including stroke, heart attack, and kidney failure. Since high blood pressure often does not cause symptoms, checkups are the best way to be sure that your treatment is working. It is very important to follow your healthcare provider’s directions and take your medicine as prescribed.

How can I take care of myself?

Follow the full course of treatment prescribed by your healthcare provider. In addition:

• Carefully follow your healthcare provider’s instructions for taking medicines. Don’t miss any doses and don’t take less medicine or stop taking medicine without talking to your provider first. It can be dangerous to suddenly stop taking blood pressure medicine. Also, do not increase your dosage of any medicine without first talking with your provider.
• Ask your provider about nonprescription medicines and supplements before you take them.
• Do not smoke.
• Follow your provider’s recommendations for physical activity. Exercise helps strengthen your heart and body and improves your blood flow and energy level. Keep a healthy weight. Lose weight if you need to.
• Eat a healthy diet that is low in salt, saturated fat, trans fat, and cholesterol. Include lots of fruits, vegetables, and fat-free or low-fat milk and milk products.
• Limit the amount of alcohol you drink.
• Check your blood pressure (or have it checked) as often as your provider advises. Keep track of the readings.
• If you have diabetes, control your blood sugar.
• Try to reduce the stress in your life or learn how to deal better with situations that make you feel anxious.

Ask your provider:

• How and when you will hear your test results
• If there are activities you should avoid and when you can return to your normal activities
• How to take care of yourself at home
• What symptoms or problems you should watch for and what to do if you have them

Make sure you know when you should come back for a checkup. Keep all appointments for provider visits or tests.