Medical terminology in this article:
Abdominal aorta: The part of the aorta that extends through the abdomen area.
Aneurysm: A weakening in the wall of a blood vessel which results in an abnormally dilated area.
Endovascular: Referred to within a vessel.
Sheath: Thin, flexible tubes
Fluoroscopy: Real time X-ray
Guidewires: Thin, flexible wire
Stent: A metal mesh tube with a layer of fabric
What is the endovascular treatment of abdominal aortic aneurysms (EVAR)?
The aorta is the largest vessel in your body and carries the blood from your heart to the rest of your organs. An aneurysm occurs if the arterial wall weakens and develops a bulge, meaning blood is flowing to the weakened area. Abdominal aortic aneurysms (AAA) are also known as ‘the silent killer’ because once they grow and rupture, there is an 80-90% risk of immediate death. EVAR is a minimally invasive procedure in which an interventional radiologist places a covered stent into the area with the aneurysm so that blood can flow through the vessel. The stent is inserted through an artery in the patient’s groin, using X-rays to guide the stent to the aneurysm.
Why perform it?
Suppose you have a small AAA it is unlikely to rupture, so it is recommended that the aneurysm is regularly monitored by a vascular expert. However, if you have a large aneurysm, or fast growing or causing symptoms such as back pain and tenderness, EVAR may be beneficial for you.
How does it work?
Usually under general anesthesia, the interventional radiologist will make a small cut at the top of each leg so it is possible to insert a short tube, which allows the vessels in your groin to be accessed safely. Using fluoroscopy for guidance, the interventional radiologist will insert guidewires and catheters. A contrast medium (dye) will be injected into the area being treated so the exact location of the aneurysm can be seen under imaging. The interventional radiologist will then use the guidewire to move a stent to the aneurysm. When the stent is placed in the correct location, it will expand, sealing the aneurysm and restoring normal blood flow through the vessel.
What are the risks?
EVAR is recommended as a preventative treatment to avoid aneurysm rupture and death. Most patients suffer no significant immediate problems, and rupture of the aneurysm is avoided in most of the patients. There are lower rates of pain and severe complications than with surgery, but the main limitations of EVAR are that the stent may slightly move or the blood may start collecting in the aneurysm again. This means that you will require regular monitoring so that if any problems do occur, they can be resolved as soon as possible.
Minor complications include the risk of bruising or groin pain. Some uncommon major complications can include infection, stroke, limb compromise, kidney injury and in rare cases paralysis. The risk of death during the procedure is nearly three times lower than the risk of dying during open surgery.