Renovascular Hypertension

Renal hypertension is caused by a narrowing in the arteries that deliver blood to the kidney. One or both kidneys' arteries may be narrowed. This is a condition called renal artery stenosis. When the kidneys receive low blood flow, they act as if the low flow is due to dehydration.

How can I prevent or slow the progression of kidney disease from high blood pressure?

being physically active.
maintaining a healthy weight.
quitting smoking.
managing stress.
following a healthy diet, including less sodium (salt) intake.

Renal hypertension (or renovascular hypertension) is high blood pressure caused by the narrowing of your arteries that carry blood to your kidneys. It is also sometimes called renal artery stenosis. Because your kidneys are not getting enough blood, they react by making a hormone that makes your blood pressure rise. This condition is a treatable form of high blood pressure when properly diagnosed.

What is high blood pressure?

Blood pressure is the force of blood against your artery walls as your heart pumps blood through your body. A reading of 120/80 mmHg, or “120 over 80,” is normal. A reading of 140/90 mmHg or above is considered high blood pressure. Blood pressure should be checked regularly.

How does high blood pressure hurt the kidneys?

High blood pressure puts increased stress on your blood vessels in the kidneys, including the filtering units that are responsible for cleaning your blood. Over time, these blood vessels can thicken, similar to other parts of the body, and the filtering units can form scars. Both of these changes can lead to your kidneys not working properly (chronic kidney disease) and they stop doing their job — removing wastes and extra fluid from your body. When your kidneys don’t work well they can cause further increases in blood pressure by releasing certain hormones or by causing retention of salt and water in your body. High blood pressure is one of the leading causes of kidney failure.

How common is renal hypertension?

Over 72 million Americans have hypertension. Less than two percent of cases are renal hypertension.

Who is more likely to have renal hypertension?

Men and women age 67 and older are more likely to have renal hypertension, but you can get it at any age. You’re more likely to have renal hypertension if you’re Caucasian instead of African American.

What causes renal hypertension?

Renal hypertension is caused by a part or total bock of the arteries that supply blood to your kidneys. These renal (kidney) arteries carry blood rich in oxygen and nutrients from your heart to your kidneys. If your kidneys do not get enough blood or oxygen, it may be because these renal arteries are narrowed, a condition called renal artery stenosis.

Atherosclerosis or hardening of the arteries

The most common cause of renal artery stenosis. Plaque, made up of fat, cholesterol, calcium and other substances, builds up inside your arteries and causes them to harden and narrow (stenosis). Plaque can block, either partially or totally, your blood's flow through an artery in the heart, brain, pelvis, legs, arms or kidneys.

Fibromuscular dysplasia (FMD)

While the cause of FMD is not clear, it is different in that it is not caused by plaque build-up, but rather narrowing of your blood vessel walls themselves. FMD is more common in women and should be considered in younger people who develop high blood pressure. Additional causes include:

Arteritides.
Radiation fibrosis.
Arteries blocked by grafts.

What symptoms or signs are seen with renal hypertension?

Although renal hypertension is hard to diagnose and usually has no symptoms, be aware of these signs:

High blood pressure that is not controlled on three or more medications at their maximum doses, including a diuretic.
High blood pressure at a young age.
Stable high blood pressure that suddenly gets worse or is difficult to control.
Kidneys that are not working well, which may occur suddenly.
Narrowing of other arteries in the body, such as to the legs, the brain, the eyes and elsewhere.
Sudden buildup of fluid inside the lungs, called pulmonary edema.

Do certain foods or drinks worsen or improve renal hypertension?

At this time there are no known foods or drinks that worsen or improve renal hypertension.

How is renal hypertension diagnosed?

It is important to see your healthcare provider regularly to make sure your blood pressure numbers are checked and are within the normal range. He or she may recommend blood tests. Imaging tests that can be done to see if the kidneys’ arteries have narrowed include:

Duplex ultrasound
Computerized tomographic angiography, or CTA
Magnetic resonance angiogram, or MRA
Catheter angiogram

What medicines may help treat renal hypertension?

If your healthcare provider suspects you might have renal hypertension, you most likely are already on medicines to help control your blood pressure. There are many different types of high blood pressure medications available. Everyone responds to medicine differently. Your healthcare provider will decide which type is best. Remember:

Many times, more than one type of medicine may be needed.
The amount and type of medicine may need to be changed from time to time.
Take all medicines in the exact way your healthcare provider prescribed them.

The goal is to lower your blood pressure. In renal hypertension, two specific types of medications may work better to control your blood pressure:

Angiotensin-converting enzyme (ACE) inhibitors.
Angiotensin receptor blockers (ARBs).

What procedures may help treat renal hypertension?

Angioplasty with stenting is an invasive procedure that helps blood flow more freely through the artery to the kidney. It is an option for those who have:

Severe narrowing of the renal artery.
Blood pressure that cannot be controlled with medicines.
Kidneys that are not working well and are rapidly becoming worse.

Is surgery necessary to treat renal hypertension?

If the condition does not improve with medication and/or angioplasty, or the narrowing recurs or cannot be stented for any reason, renal bypass surgery may be an option. By taking a vein or synthetic tube to connect your kidney to your aorta, the surgeon creates an alternate route, or bypass, for blood to flow around the blocked artery into your kidney. This procedure is complex and high risk and rarely used.

How does the success of medicine compare with the success of procedures?

Angioplasty and stenting have not been shown to be better than controlling blood pressure with medications. This is because, in most people, renal artery stenosis may be present but does not cause high blood pressure. In such cases, opening up the artery will not result in improved blood pressure. It is suggested that this procedure be reserved for those whose blood pressure cannot be controlled by medications, who experience unacceptable side effects with their blood pressure medications, who developed rapidly worsening kidney function or who have a rapid build-up of fluid in their lungs called flash pulmonary edema.

What can I do to help relieve the symptoms of renal hypertension?

There are no at-home remedies that can help with renal hypertension. However, you should always take your medicines as prescribed, eat healthy and follow your healthcare provider’s instructions.

Is renal hypertension curable?

In theory, if the renal artery stenosis is reversed, then the hypertension should improve.

Are there complications?

If you have renal hypertension, you might experience the following complications that are caused by high blood pressure, including:

Renal failure.
Myocardial infarction.
Stroke.
Pulmonary edema.
Retinopathy.
Left ventricular hypertrophy.
Congestive heart failure.
Aneurysm.
Vascular dementia.

What can I do to help control my high blood pressure?

A healthy lifestyle is key to helping control any type of hypertension. Making changes in daily habits can help, such as:

Eating a heart-healthy diet: Choose fruits, vegetables, grains and low-fat dairy foods.
Exercising regularly, at least 30 minutes a day of moderate activity, such as walking (check with your healthcare provider before starting an exercise program).
Keeping your weight under control: Check with your healthcare provider for a weight-loss program, if needed.
Quitting smoking, if you smoke.
Cutting back on beverages that contain alcohol.
Limiting caffeine intake.
Limiting sodium (salt) in your diet: Read nutrition labels on packaged foods to learn how much sodium is in one serving.
Reducing and avoiding stress when possible: Many people find that regular meditation or yoga helps.

Is renal hypertension fatal?

If you don’t get your renal hypertension treated, you might end up having end-stage renal failure (your kidney will not work anymore). The median survival time of someone with end-stage renal failure is about two years.

How do I take care of myself?

Take your medicines and do your best to keep your blood pressure low. Keep your body healthy by eating right, exercising and quitting smoking. Follow up with your appointments with your healthcare provider. What questions should I ask my healthcare provider about renal hypertension?

How high is my blood pressure?
What medications should I be on?
Should I have surgery?

Key Takeaways Renal hypertension is a very serious disease. You and your healthcare provider need to pay close attention to your blood pressure. High blood pressure (hypertension) can cause heart attack, aneurysm and stroke, among other complications. Work with your healthcare provider to figure out the best treatment and be sure to take all medications and follow all post-operative instructions perfectly.