Diagnosis
To diagnose renal artery stenosis, your healthcare professional may start with:
- A physical exam. This includes listening through a stethoscope over the kidneys for sounds that may mean the artery to the kidney is narrowed.
- A review of your medical history.
- Blood and urine tests to check how your kidneys work.
- Blood and urine tests to measure the levels of hormones that keep blood pressure managed.
Your healthcare professional might order the following imaging tests:
- Doppler ultrasound. High-frequency sound waves help a healthcare professional see the arteries and kidneys and check how they work. This procedure also helps find if the blood vessels are blocked and measure how bad the blockage is.
- CT scan. This is a type of imaging that uses X-ray techniques to make detailed images of the body. It then uses a computer to make cross-sectional images, also called slices, of the renal arteries. You may get a shot of dye, called an injection, to show blood flow.
- Magnetic resonance angiography. Also called MRA, this uses radio waves and strong magnetic fields to make detailed images of the renal arteries and kidneys. A shot of dye into the arteries outlines blood vessels during imaging.
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Renal arteriography. This special type of X-ray exam helps find the blockage in the renal arteries. Sometimes, a healthcare professional uses this to open the narrowed part with a balloon or small tube, called a stent.
Before the X-ray, a member of your healthcare team puts a dye into the renal arteries through a long, thin tube, called a catheter. This is to outline the arteries and show blood flow more clearly. This test mainly is for people who are likely to need to have a stent widen an artery.
Treatment
Treatment for renal artery stenosis may involve lifestyle changes, medicine and a procedure to restore blood flow to the kidneys. If your arteries are not blocked, you may not need treatment.
Lifestyle changes
If your blood pressure is too high, lifestyle changes may help manage your blood pressure. This includes limiting salt, eating healthy foods and moving more.
Medication
Medicine can often treat high blood pressure linked to renal artery stenosis. It may take time and patience to find the right medicine or mix of medicines.
Medicines that often treat high blood pressure linked with renal artery stenosis and may keep kidney disease from getting worse include:
- Angiotensin-converting enzyme inhibitors, also called ACE inhibitors, and angiotensin II receptor blockers, also called ARBs. These medicines relax blood vessels and keep them from narrowing.
- Diuretics. Also called water pills, these help the body get rid of salt and water.
- Beta blockers and alpha-beta blockers. These either make the heart beat slowly with less force or they widen, called dilate, the blood vessels. The effect depends on which medicine you take.
- Calcium channel blockers. These medicines help relax blood vessels.
If atherosclerosis is the cause of renal artery stenosis, your healthcare professional also may suggest that you take aspirin and a cholesterol-lowering medicine.
Procedures
Some people may have a procedure to restore blood flow through the renal artery. Called renal angioplasty, this improves blood flow to the kidney.
This procedure may be for people who don't do well on medicine alone, who can't take medicine, who often retain fluids or who have heart failure that's hard to treat.
Procedures to treat renal artery stenosis may include:
- Renal angioplasty and stenting. This procedure involves widening the narrowed renal artery and putting a tube called a stent inside the blood vessel. The stent holds the walls of the vessel open and lets blood flow better. If you have a condition called fibromuscular dysplasia, your healthcare team may widen the kidney artery without adding a stent.
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Renal artery bypass surgery. During a bypass procedure, a surgeon adds another blood vessel to the renal artery to make a new route for blood to reach the kidneys. This may mean joining the renal artery to a vessel from elsewhere in the body, such as the liver or spleen.
Surgeons do this procedure mainly if angioplasty doesn't work or when there's a need for more surgical procedures.
Lifestyle and home remedies
As a part of your treatment plan for renal artery stenosis, your healthcare professional may suggest these lifestyle changes:
- Get to and stay at a healthy weight. When weight goes up, so does blood pressure. If you're overweight, losing weight may help to lower your blood pressure.
- Use less salt in your diet. Salt and salty foods cause your body to retain fluid. This may increase your blood pressure.
- Be physically active. Being physically active may help you lose weight, lower your risk of heart disease, and lower your cholesterol and your blood pressure. Check with your healthcare professional before starting an exercise program.
- Don't use tobacco. Tobacco harms blood vessel walls and speeds up the process of hardening of the arteries. If you smoke, ask your healthcare team to help you quit.
Preparing for your appointment
For renal artery stenosis, you may start by seeing your main healthcare professional. Your healthcare professional may send you to a doctor who specializes in conditions that affect the kidneys, called a nephrologist, or a heart and blood vessel specialist, called a cardiologist.
Here's some information to help you get ready for your appointment.
What you can do
Ask a family member or friend to go with you to help you gather what you learn.
Make a list of:
- Your symptoms, and when they began. Include symptoms that don't seem linked to the reason you made the appointment.
- Make a list of all medicines, vitamins and supplements that you take, including dosages.
- Key medical information, including past or current smoking or use of other tobacco products.
- Questions to ask your healthcare professional.
For renal artery stenosis, basic questions to ask include:
- What's the most likely cause of my symptoms?
- What tests do I need? How do I prepare for them?
- Is this condition likely to go away or to last?
- What treatments are there? Which do you suggest?
- I have other health conditions. How can I best manage these conditions together?
- What's a good level for my blood pressure? What can I do to help bring it down?
- Do you have any printed material that I can have? What websites do you suggest?
Be sure to ask all the questions you have.
What to expect from your doctor
Your healthcare professional is likely to ask you questions, such as:
- Do you smoke or use any type of tobacco or have you ever?
- Does anything seem to make your symptoms better or worse?
- Do you know what your blood pressure most often is?
- Have you had tests to measure how your kidneys work?
- Does anyone in your family have a history of high blood pressure or kidney disease?