Renal Artery Stenting

What is renal artery stenting?

Renal artery stenting is a procedure that opens up blockages in your renal arteries — the large blood vessels that carry blood to your kidneys — as a result of renal artery stenosis. Renal artery blockages affect how blood flows to your kidneys. Stenting opens the blockage and can restore normal blood flow.

Your kidneys help control the amounts of salt and fluid in your body by filtering blood and making urine (pee). When blood can’t get to your kidneys to remove salt and water, fluid builds up in your body.

Your kidneys also release renin. Renin is a hormone that helps tell your body to keep salt and water. It also causes the blood vessels in your body to become more rigid (stiff). When your kidney senses lower blood pressure, it increases the amount of renin that it releases. A narrowed kidney artery (renal artery) tells your kidney the blood pressure is low when in fact it may be very high.

Together, this results in renal hypertension, which is a type of high blood pressure. High blood pressure puts extra strain on your heart and other organs. Renal hypertension can lead to kidney failure.

Why do they put stents in kidneys?

A healthcare provider will put stents in one or both of your renal arteries if they determine you have a significant blockage that requires treatment. The renal stents help prevent any further damage to your kidneys. However, not all blockages in your renal artery require stenting.

When is a stent needed for a renal artery?

You may need a kidney stent if you have atherosclerosis (plaque collecting inside your artery) that causes a blockage within the artery greater than 60% that you can’t manage with medicines. You may be a good candidate for renal artery stenting if you have unmanaged blood pressure while taking high doses of three or more blood pressure medications.

How often is renal artery stenting performed?

Healthcare providers perform renal artery stenting less often today than in the past. Several large trials demonstrated that there aren’t significant benefits to renal artery stenting. But these trials didn’t include people who are most likely to benefit from renal artery stenting. This includes people with:

• A blockage of 60% or greater in both renal arteries.
• Only one renal artery that has a blockage of greater than 60%.
• Problems with rapid fluid buildup in their lungs (flash pulmonary edema).
• Blood pressure they can’t manage with three or more medicines.

What happens before renal artery stenting?

Before renal artery stenting, you’ll meet with a healthcare provider. They’ll check your general health and take your vitals (temperature, pulse and blood pressure). They’ll also use certain tests to see if you need renal artery stenting. These tests may include:

• Duplex Doppler ultrasonography. This test uses sound waves to measure the size of the blockage and the speed at which your blood flows within your renal arteries.
• Computed tomography angiogram. A computed tomography scan (CT scan) uses a series of X-rays to build a 3D image of your kidneys. A CT scan also uses contrast dye to highlight your renal arteries.
• Magnetic resonance angiogram (MRA). An MRA is similar to magnetic resonance imaging (MRI), which uses a large magnet to create images inside your body. With an MRA, a provider injects contrast dye into your blood. The contrast dye allows the provider to see your blood vessels.
• Angiogram. During an angiogram, a provider inserts a catheter through your groin into your aorta, which is the main artery in your body. The catheter advances to your renal arteries and then releases a contrast material (dye) into your blood. The contrast dye allows the provider to see how well blood flows through your arteries.

Tell your healthcare provider about any prescription or over-the-counter (OTC) medications you’re taking. These include herbal supplements. Aspirin, anti-inflammatory drugs, certain herbal supplements and blood thinners can increase your risk of bleeding. Be sure to check with a healthcare provider before stopping any medications.

Tell your healthcare provider about any allergies you have, as well. Include all known allergies. These include allergies to medications, skin cleaners like iodine or isopropyl alcohol, latex and foods.

Your healthcare provider will also give you specific directions on eating and drinking before your procedure.

Are you put out for a kidney stent?

Not usually. Before the procedure, a healthcare provider will insert an intravenous (IV) line into a vein in the back of your hand or arm to deliver pain medication and sedatives to your bloodstream. The sedatives help you relax before the surgery without being completely asleep. You likely won’t remember anything about the procedure while you’re under sedation.

What happens during renal artery stenting?

Renal artery stenting takes place during an angiogram.

Your provider makes a tiny (usually less than an eighth of an inch) incision in your groin or arm.

Through this incision (cut), they insert a hollow tube, or sheath, into the artery in your groin or arm. They then place another type of hollow tube (catheter) into your affected renal artery through the sheath.

Once they reach the affected area of your renal artery, they may inflate a balloon to open the blockage to make room for the stent. The stent is a metal, fine mesh tube. They’ll place it across the renal artery blockage and then deploy it. It presses against the renal artery wall to move the blockage out of the way and create a larger channel for blood flow to get to your kidney. The stent stays in your body in order to maintain blood flow.

Once the stent is in place, they’ll deflate the angioplasty catheter, remove it and hold pressure over the incision or use a specialized device to close the opening in the artery. They’ll then place a bandage over the incision.

What happens after renal artery stenting?

After renal artery stenting, you’ll recover at the hospital for at least a few hours. You may need to stay overnight. Healthcare providers will track your overall health, treat your pain and monitor your blood pressure levels. They may adjust your medications before letting you go home (discharge), which they’ll review with you.

Once your providers determine you’re healthy enough and no longer require monitoring, they’ll discharge you. You must have a family member or friend drive you home.

What are the advantages of renal artery stenting?

Renal artery stenting advantages include:

• It’s a minimally invasive procedure with a low risk of side effects.
• It helps blood flow better through your affected renal arteries.
• It may decrease blood pressure.
• It may help preserve kidney function.

What are the risks of renal artery stenting?

The risks of renal artery stenting include:

• Bruising where your provider inserts the sheath and catheter.
• Bleeding in or around the insertion site.
• Damage to your renal artery or kidney.
• Blood clots.
• An allergic reaction to the contrast dye.
• Stent misplacement.
• Kidney failure.

What is the recovery time after renal artery stent placement?

Most people feel better a few days after renal artery stent placement. Your healthcare provider will tell you how active you should be for the first few days after the procedure.

You may need to take a blood-thinning medicine to help your blood flow properly and prevent blood clots until the area around your stent heals. These medicines may include aspirin or clopidogrel. Depending on your bleeding risk, you may need to take these medicines for a month or up to a year. It’s very important that you take them, and you shouldn’t stop taking them without first talking to your provider.

When can I go back to work or school?

Most people can return to work or school within a week after the procedure. If you have a physically demanding job that requires a lot of heavy lifting, you may need to take more time off to heal.

When should I see my healthcare provider?

Sometimes, new blockages can develop in a different area of your renal artery. An artery can narrow again (restenosis), so it’s important to see your healthcare provider for all follow-up appointments.

You should also call your provider if:

• You develop a fever.
• You have problems breathing.
• You develop a rash.
• The area where your provider inserted the catheter becomes discolored (red, purple, dark brown or black), swollen or painful or it oozes blood.
• The leg in which the catheter was inserted becomes painful, cold, pale or weak.
• You notice new pain in your abdomen or on the side in which you received treatment.
• You become lightheaded and have very low blood pressure (hypotension).

Will renal artery stenting cure renal artery stenosis?

Renal artery stenting fixes renal artery stenosis by enlarging a channel that allows for a lot more blood to reach the kidney. But there are multiple causes of high blood pressure, and it successfully treats only about a third of people who have hypertension or high blood pressure.

Over time, the renal artery stenosis can come back. After the procedure, a healthcare provider must periodically monitor the stent. Most people with renovascular hypertension will need to continue taking at least some blood pressure medicines even after receiving a stent.

How long do renal stents stay in?

Renal stents are permanent implants.

Are renal stents painful?

Renal artery stents aren’t typically painful. Some people have mild discomfort during placement. But after placement, you shouldn’t notice that you have a renal stent.