Endovascular Aneurysm Repairs
An endovascular stent graft is a metal-lined fabric tube that reinforces an aneurysm in a blood vessel. It is a way to reline the blood vessel and decrease the chance of an aneurysm rupturing. The stent graft seals tightly above and below the aneurysm. The graft is stronger than the weakened artery and allows blood to pass through it without pushing on the bulge. Endovascular stent grafting can be used to treat abdominal aortic aneurysms (AAAs), as well as thoracic aortic aneurysms (TAAs).
The aorta is the large blood vessel that comes out of your heart. It transports blood to the rest of the body. The aorta can become weakened in certain parts that then grow and dilate. These aneurysms can become large enough that they may be at risk for rupture and possibly death. The decision to repair an aneurysm will be made by your physician based on the anuerysm's size, location and rate of growth. Not everyone is a candidate for endovascular repair as the grafts must be specially fit to the anatomy of each patient's aorta.
To perform endovascular procedures, vascular surgeons and interventional radiologists use wires and catheters inside the blood vessels. Theses catheters can be placed in the blood vessels in the legs, meaning that only two small incisions are required. Generally, endovascular treatments allow you to leave the hospital sooner and recover more quickly, with less pain and a lower risk of complications and death than traditional surgery, because the incisions are smaller. Sometimes traditional surgery is required, however, if the shape or the location of the aneurysm is not favorable for an endovascular treatment.
What is the Evaluation?
We will talk to you about your medical history and perform a complete physical examination. In addition, we may perform several tests to evaluate the health of your heart. If you are a good candidate for endovascular stent grafting, we will order one or more of the following tests. These tests show detailed images of your arteries and help us choose the correct size and shape of the graft:
Computed tomography (CT) scan:
This test involves a rapid series of x- rays taken in a spiral pattern around your body. A computer transforms the x ray data into three-dimensional images of your blood vessels.
An interventional radiologist will inserts a catheter into one of your femoral arteries. Through this catheter, contrast will be administered to define the anatomy of your blood vessels.
Will I be eligible for endovascular stent grafting?
You may be eligible for endovascular stent grafting if your aneurysm measures 5 cm wide or more. However, if you have a long life expectancy and are relatively healthy, we may recommend surgical aneurysm repair instead. This treatment has been used more often and its risks and benefits are better known.
The physical characteristics of your aneurysm help us to determine if you are eligible for endovascular treatment. For example, if you have an AAA located in the section of the aorta just below your kidney arteries, you may be eligible. Your blood vessels must be large enough to allow the catheters to pass through, and the device must fit the shape and contour of your blood vessels once it is in place.
What happens during endovascular stent grafting?
As the procedure begins, you will receive a sedative and regional anesthesia, or you may receive general anesthesia. Your vascular surgery team will clean your skin and shave hair around the insertion points to help decrease your chances of infection. We will then make small incisions above the femoral artery in your groin. A guide wire will be threaded into your femoral artery and advanced to the aneurysm. Because you have no nerve endings inside your arteries, you will not feel the wires or catheters as they move through your body. You may feel a slight pressure or sensation of mild tugging during this insertion.
Using x-rays that appear as moving images on a screen, we will insert a catheter over the wire. The catheter carries a compressed form of the graft so it can move through your blood vessels. When the graft has reached the aneurysm site, we will withdraw the catheter, leaving the graft in place. The graft expands to fit snugly against the walls of your artery.
What can I expect after endovascular stent grafting?
Usually you will spend 1 to 2 days in the hospital. During the first recovery day you will be permitted to eat and perhaps walk.
After you leave the hospital, you should not drive until we have insured that you are safe to do so. You can sponge bath around your incisions but you should avoid soaking your groin incisions until they have healed. You should also avoid lifting more than about 5 pounds for approximately 6 weeks after the procedure.
We will instruct you to return for a follow-up visit after about 7 to 10 days. At that visit, we will check your incisions and assess your overall condition.
You will undergo follow-up imaging tests 1 and 6 months after the procedure to ensure that the stent is still functioning and in the proper location. If there are no problems, you will undergo yearly CT scans.
Are there any complications?
The potential complications of endovascular stent grafting include:
- Leaking of blood around the graft (known as an endoleak)
- Movement of the graft away from the desired location (known as migration)
- Blockage of the blood flow through the graft
Sometimes fever and an increase in white blood cell count can happen shortly after endovascular stent grafting. These symptoms usually last 2 to 7 days and are treated with medications such as aspirin and ibuprofen. Other complications that are rare but serious include a burst artery, injury to your kidney, blocked blood flow to your abdomen or lower body, and delayed rupture of AAA.
Endovascular stent grafts can sometimes leak blood through the areas where the graft components join together, but also they can allow blood to leak back into the aneurysm sac through small arteries feeding the aneurysm sac. These are called endoleaks. Some of these leaks go away by themselves and are not dangerous, but others need to be treated. These leaks can even occur years after your procedure. Yearly CT scans will help to detect and treat problems before they become threatening.