Let's learn about placing stents in the veins leading to the kidneys? (Renal Artery Stenting)

Do you also have high blood pressure? You may be taking more than one type of medication to control your blood pressure. But if you still have difficulty controlling your blood pressure, the cause may be a blockage in the arteries that supply blood to your kidneys. So today, let's talk about the treatment called 'Renal Artery Stenting' that is used in such cases. Don't be scared when you hear this, let's understand everything about it simply.

What is Renal Artery Stenting?

Simply put, the main blood vessels that carry blood to the two kidneys in our body are called 'renal arteries'. Just like the two main pipes that carry water to a garden. Sometimes, things like fat build up inside these blood vessels (this condition is called `(Atherosclerosis)`) and the passage inside the veins becomes narrow. We call this 'renal artery stenosis'.

Imagine something like a water pipe getting clogged with rust. Then the water's path gets narrowed, right? In the same way, the path to the kidneys gets blocked.

Renal Artery Stenting is a treatment that is used to reopen, or keep open, a blocked blood vessel. In this, a very small, mesh-like metal tube (stent) is inserted into the blocked area, opening the vein. Then, blood starts flowing well to the kidney again.

What actually happens when the renal veins are blocked?

As you know, one of the main functions of our kidneys is to filter the blood and remove unnecessary salts and fluids from the body as urine. When the amount of blood flowing to the kidneys decreases, they cannot do this job properly. Then, fluid begins to accumulate in the body.

Not only that, but something else important happens. When the kidney 'senses' that there is less blood flowing to it, it thinks that the blood pressure in the whole body has decreased. So, to increase the blood pressure, the kidney releases a special hormone called `(renin)`. This hormone causes the blood vessels in the body to tighten. But what actually happens is that the blood pressure in the body may be at a very high level at that time.

Who needs a stent?

Not everyone with a blocked renal artery will need a stent. Your doctor will only recommend this treatment in certain special cases.

What tests are done before stenting?

Before deciding to place a stent, your doctor will do several tests to determine how blocked your artery really is.

• Duplex Doppler Ultrasonography: This is like a regular scan. It uses sound waves to measure how narrowed the artery is and how fast the blood is flowing.
• Computed Tomography Angiogram (CT Angiogram): This involves injecting a special dye into your veins and using a CT scanner to take a three-dimensional (3D) picture of the veins. This allows you to clearly see where the veins are blocked.
• Magnetic Resonance Angiogram (MRA): This is similar to an MRI scan. A dye is injected and a magnetic field is used to create clear images of the blood vessels.
• Angiogram: This is the most accurate method. In this, a very thin tube (catheter) is inserted through a vein in the groin or arm and guided to the renal vein. Then, a dye is injected through it and an X-ray is taken to see how the blood is flowing. Stenting is usually done during this test.

Important: Before these tests, you must tell your doctor about all medications you are taking (especially blood thinners like aspirin) and any allergies you may have.

How is stenting surgery performed?

This is not a major open surgery. You are not put to sleep. You are given a medicine called `sedation` to make you relaxed and sleepy. So you don't feel any pain and you don't have any memory of it afterwards.

The treatment is simply as follows:

1. A very small incision (a few millimeters) is made in the skin of your groin or arm.

2. Through it, a flexible tube (sheath) is inserted into the vein.

3. Through that tube, another very thin tube (catheter) is passed to the blocked vein in the kidney.

4. Then, a small balloon at the end of the tube is inflated to widen the blocked area.

5. Finally, the mesh-like stent we talked about earlier is placed in the widened area. The stent presses against the wall of the artery, keeping the artery open.

6. The stent is permanently placed there, the balloon and tube are removed, the incision is closed, and a bandage is applied.

What are the benefits and risks after treatment?

As with any medical treatment, there are both benefits and minor risks.

After the treatment, you will have to stay in the hospital for a few hours or maybe even overnight. After going home, you should be back to normal within a few days. You can resume your normal activities in about a week. The most important thing is to take the blood-thinning medication (such as `Aspirin`, `Clopidogrel`) that your doctor prescribes for the exact amount of time. Never stop taking the medication without asking your doctor.

When should I see the doctor again?

Even after the stent is placed, you should definitely go for follow-up visits as the doctor recommends, because sometimes the stent or another area can become blocked again.

If any of the following symptoms occur, call your doctor immediately:

• If you get a fever.
• If you have difficulty breathing.
• If a skin rash occurs.
• If the area where the tube was inserted is red, swollen, painful, or if there is blood or pus draining from there.
• If the leg on the treated side becomes painful, cold, or pale.
• If you develop new pain in your stomach or on the treated side.
• If you feel dizzy and your blood pressure drops a lot.

The stent is a permanent part of the body. It is usually painless. While it can help many people control their high blood pressure, you may still need to take medication to control your blood pressure. Your doctor will decide this based on your condition.

Renal Artery Stenting, renal artery, high blood pressure, renal hypertension, stent, angioplasty, kidney disease