Renovascular Hypertension

Renovascular hypertension (also called renal hypertension) is high blood pressure that’s related to problems in your kidneys. It occurs when the arteries that carry blood to your kidneys become narrow.

As your renal arteries narrow, less blood can flow through. This means your kidneys receive less blood than they should. In response, they activate a system of hormones and other substances called the RAAS. The RAAS raises blood pressure throughout your body.

Renovascular hypertension is a common form of secondary hypertension. It’s also a frequent cause of resistant hypertension. Knowing your high blood pressure is related to your kidneys can help your provider treat it more effectively.

Symptoms of renovascular hypertension

Renal hypertension usually won’t cause you symptoms. Instead, healthcare providers look for details in your medical record that suggest you might have this condition.

Here are some possible signs of renal hypertension:

• High blood pressure that starts before age 30 or after age 50
• Blood pressure that was well managed for a while but suddenly goes up
• Blood pressure that’s not going down even though you’re taking multiple medicines for it
• Several episodes of a hypertensive crisis
• Episodes of “flash” (sudden) pulmonary edema
• A history of plaque buildup in other arteries, like those in your heart, neck or legs
• Chest pain without any significant plaque buildup in your coronary arteries
• Kidney failure for no known reason
• A whooshing sound (bruit) that your provider hears when listening to blood flow in your belly

Renovascular hypertension causes

Renal artery stenosis is the main cause of renovascular hypertension. This is a narrowing of the arteries that carry blood to your kidneys. It can happen due to plaque (atherosclerosis) or abnormal cell growth in the artery walls (fibromuscular dysplasia).

Less common causes of renovascular hypertension include:

• Vasculitis
• Renal artery aneurysm
• A tumor pressing on your kidney or renal artery
• Scarring (fibrosis) from radiation therapy

Complications of renovascular hypertension

Any form of hypertension — including renovascular — can lead to hypertensive heart disease. This is when high blood pressure that lasts a long time damages your heart. Untreated high blood pressure can also lead to other complications, like kidney disease or retinal disease.

How doctors diagnose this condition

Healthcare providers diagnose renovascular hypertension by putting together lots of clues. They get these clues from:

• Doing a physical exam
• Reviewing your medical history
• Running tests

Tests you may need include:

• Blood tests
• Urine tests
• Kidney ultrasound and possibly other imaging tests that show blood flow in your renal arteries
• Imaging tests that show blood flow in other parts of your body, like your carotid arteries

How is renovascular hypertension treated?

Treatment usually involves medications to lower your blood pressure and support blood flow. Usually, treatment with medicine is enough. But sometimes, providers recommend a procedure or surgery to improve blood flow to your kidneys.

Medications

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

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

These medications act on your RAAS to keep it from raising your blood pressure.

In addition to an ACE inhibitor or ARB, you may need other medications, too, like statins, calcium channel blockers or diuretics. Your provider will explain exactly which medications you need and why.

Procedures

Providers treat renal hypertension with renal artery angioplasty (sometimes with stenting) in certain situations. These include:

• You have renal hypertension due to fibromuscular dysplasia
• Medications aren’t enough to lower your blood pressure
• You develop congestive heart failure or pulmonary edema without a known cause.

A newer treatment that’s been approved to treat certain types of hypertension is called renal denervation. In this procedure, heat or ultrasound energy can be used to reduce the activity of the nerve endings in your renal arteries. This may help to lower your blood pressure.

For any procedure, your provider will explain the benefits, risks and recovery so that you understand exactly what’s involved.

Surgery

Rarely, providers recommend surgery for renal hypertension. This is called surgical renal revascularization, or renal bypass surgery.

Your surgeon uses part of another blood vessel or a synthetic tube to connect your aorta to your kidney. This creates a new path for blood to flow directly to your kidney. Blood can avoid (bypass) your narrowed renal artery.

Surgery is riskier than angioplasty and stenting. So, providers only use it in certain situations, like:

• You have complex renal artery anatomy that doesn’t allow a stent
• Minimally invasive methods didn’t work
• You need surgery on your aorta near your renal arteries

When should I see my healthcare provider?

Your provider will tell you how often to come in for follow-up appointments. These give your provider a chance to:

• Check your blood pressure to see how well treatment is working
• Check your kidney function
• Adjust your treatment plan as needed

These appointments also give you a chance to ask your provider questions and share any concerns.

Can renal hypertension be cured?

Renovascular hypertension is a treatable form of high blood pressure. This means medicines and other treatments may lower your blood pressure to a healthy range. Your healthcare provider can tell you more about what you might expect in your situation.

In general, it’s important to:

• Take all your medicines exactly as your provider prescribes them
• Follow your provider’s guidance for foods to eat or avoid (they may recommend the DASH diet)
• Talk to your provider about the amount of physical activity you should aim for