Read more about what happens when the arteries leading to your kidneys become narrowed, as well as potential treatments for this condition.
Renal artery stenosis is the narrowing of one or more arteries that carry blood to your kidneys (renal arteries).
Narrowing of the arteries prevents enough oxygen-rich blood from reaching your kidneys. Your kidneys need adequate blood flow to help filter waste products and remove excess fluids. Reduced blood flow to your kidneys may injure kidney tissue and increase blood pressure throughout your body.
In renal artery stenosis, one or both of the arteries leading to the kidneys becomes narrowed, preventing adequate blood flow to the kidneys.
Renal artery stenosis often doesn't cause any signs or symptoms until it's advanced. The condition may be discovered incidentally during testing for something else. Your health care provider may also suspect a problem if you have:
As renal artery stenosis progresses, other signs and symptoms may include:
Make an appointment with your doctor if you have any persistent signs or symptoms that worry you.
The two main causes of renal artery stenosis include:
Fibromuscular dysplasia. In fibromuscular dysplasia, the muscle in the artery wall doesn't grow as it should. This often begins in childhood. The renal artery can have narrow sections alternating with wider sections, giving a bead-like appearance in images of the artery.
The renal artery can narrow so much that the kidney doesn't get enough blood. This can lead to high blood pressure at a young age. This can happen in one or both kidneys. Experts don't know what causes fibromuscular dysplasia, but the condition is more common in women and may be something that's present at birth (congenital).
Narrowed kidney arteries and fibromuscular dysplasia can affect other arteries in your body as well as your kidney arteries and cause complications.
Rarely, renal artery stenosis results from other conditions such as inflammation of the blood vessels or a growth that develops in your abdomen and presses on your kidneys' arteries.
Most cases of renal artery stenosis result from narrowed kidney arteries. Risk factors that make narrowed arteries more likely in your kidneys and other parts of your body include:
Possible complications of renal artery stenosis include:
For diagnosis of renal artery stenosis, your health care provider may start with:
Imaging tests commonly done to diagnose renal artery stenosis include:
Treatment for renal artery stenosis may involve lifestyle changes, medication and a procedure to restore blood flow to the kidneys. Sometimes a combination of treatments is the best approach. Depending on your overall health and symptoms, you may not need any specific treatment.
If your blood pressure is moderately or severely elevated, a healthy lifestyle — limiting salt, eating healthy foods and getting regular physical activity — can help control your blood pressure.
High blood pressure — even when mainly related to renal artery stenosis — often can be successfully treated with medications. Finding the right medication or combination of medications may require time and patience.
Some medications commonly used to treat high blood pressure associated with renal artery stenosis include:
If atherosclerosis is the underlying cause of renal artery stenosis, your provider may also recommend aspirin and a cholesterol-lowering medication. Which medications are best for you depends on your individual situation.
For certain people a procedure may be recommended to restore blood flow through the renal artery to improve blood flow to the kidney.
Results from clinical trials comparing medication with renal angioplasty and stenting didn't show a difference between the two treatment approaches on reducing high blood pressure and improving kidney function for people with moderate renal artery stenosis. Procedures to open the vessel should be considered for people who don't do well on medicine alone, who can't tolerate medications, who often retain fluids and who have treatment-resistant heart failure.
Procedures to treat renal artery stenosis may include:
As a part of your treatment plan for renal artery stenosis, your doctor may recommend making certain lifestyle changes:
For renal artery stenosis, you may start by seeing your family doctor or a general practitioner. However, you may be referred to a doctor who specializes in conditions that affect the kidneys (nephrologist) or a heart and blood vessel specialist (cardiologist), particularly if blood pressure is difficult to control or kidney function worsens.
Here's some information to help you get ready for your appointment, as well as what to expect from your doctor.
To prepare for your appointment:
For renal artery stenosis, some basic questions to ask your doctor include:
In addition to the questions that you've prepared, don't hesitate to ask other questions as they occur to you during your appointment.
Your doctor is likely to ask you a number of questions, such as: