Endovascular Stent Graft
What is an endovascular stent graft?
An endovascular stent graft is a fabric tube supported by a metal framework. It is used most commonly to reinforce a weak spot in an artery called an aneurysm. If left untreated, this weak area can bulge like a balloon and it can eventually enlarge and rupture. The stent graft is designed to seal tightly with your artery above and below the aneurysm and allow blood to pass through without pushing on the bulge. Physicians use endovascular stent grafting to treat abdominal aortic aneurysms (AAAs), thoracic aortic aneurysms (TAAs), and, less commonly, aneurysms in other locations.
Aortic aneurysms are potentially serious health problems since a burst aorta results in massive internal bleeding that can cause death unless treated rapidly by an experienced medical team. Endovascular stent graft repair is designed to help prevent an aneurysm from bursting. The term “endovascular” means "inside blood vessels." To perform endovascular procedures, vascular surgeons use special technologies and instruments that require only a small incision or puncture in an artery or vein. Through these punctures, a surgeon inserts devices through your blood vessels to the location of the aneurysm to strengthen your artery. Compared to traditional surgery, endovascular treatments generally allow you to leave the hospital sooner and recover more quickly, with less pain and a lower risk of complications, 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. Your vascular surgeon will help you decide which procedure is best for your particular situation.
Am I eligible for endovascular stent grafting?
The physical characteristics of your aneurysm help your physician determine if you are a good candidate for endovascular treatment. You may be eligible for endovascular stent grafting if you have a long enough area of normal artery above and below the aneurysm for the stent graft to attach securely. For example, if you have an AAA located in the section of the aorta just below your kidney arteries, and there is enough space for the stent graft to seal properly, and your aorta is not severely angled, you may be eligible. Your blood vessels also must be large enough to allow the endovascular stent graft to pass through, and the device must fit the shape and contour of your blood vessels once it is in place. Stent grafting is not limited to the aorta, but may also be an option for aneurysms in other regions of the body. Your vascular surgeon will best be able to determine whether your specific aneurysm is amenable to stent graft therapy. click image to enlarge
How do I prepare?
Your physician will ask you about your medical history and perform a complete physical examination. In addition, your physician may perform several tests, including a scan to determine if your aneurysm has a favorable shape for endovascular stent graft treatment.
Am I at risk for complications?
If you have kidney disease, your chances of complications from endovascular stent grafting may be increased since contrast dye, which can affect the kidneys, is required. If you have an unfavorable aneurysm shape, associated arterial occlusive disease, or have already had an AAA repaired, you also may be at increased risk for complications. Other conditions, such as heart or lung disease, may also increase the risk for treatment.
What happens during endovascular stent grafting?
As the procedure begins, you will usually receive anesthesia. Your vascular surgeon may cut into the skin overlying the femoral artery in your groin or, depending upon the type of stent graft being used, a puncture may be made directly through the skin. Your surgeon then threads a guide wire into your femoral artery and advances it to the aneurysm. Using x-ray as a guide, a compressed form of the graft is passed over the wire into your blood vessels. When the graft has reached the aneurysm site, the graft expands to fit snugly against the walls of your artery. Often, additional components of the graft are placed through incisions in each groin to extend to the arteries supplying each leg. click image to enlarge
What can I expect after endovascular stent grafting?
Usually you will spend 1 to 2 days in the hospital. After you leave the hospital, you should not drive until your physician approves. You may be permitted to sponge bathe around your incisions but you should avoid soaking your groin incisions until they have healed. You may also be advised to avoid lifting more than about 5 to 10 pounds for approximately 4 weeks after the procedure. Your physician will instruct you to return for a follow-up visit within the first few weeks after your procedure. At that visit, your physician will check your incisions and assess your overall condition. Usually you will undergo follow-up imaging tests within the first few months after the procedure to ensure that the stent is functioning without significant problems and in the proper location. After the first year, you will probably undergo yearly imaging tests if your aneurysm is shrinking and no problems are found. You may require more frequent imaging tests if potential problems require closer monitoring.
Are there any complications?
The potential complications of endovascular stent grafting include:
- Leaking of blood around the graft (“endoleaks”)
- Movement of the graft away from the desired location (“migration”)
- Blockage of the blood flow through the graft Other complications that are rare but serious include a burst artery, injury to your kidney, paralysis, and blocked blood flow to your abdomen or lower body.
Endovascular stent grafts can sometimes fail to completely seal off the aneurysm, which is called an “endoleak”. While this name is somewhat confusing, it does not imply that your aneurysm has ruptured or is leaking. Some of the leaks stop by themselves and are not dangerous, but others need to be treated immediately. These leaks can even occur years after your procedure and can be dangerous if the aneurysm continues to enlarge. Thus, after endovascular aneurysm repair, physicians require their patients to undergo long term surveillance with periodic scans for the rest of their life. Since problems with the graft or endoleaks can occur even years after successful placement, it is important to comply with the follow-up regimen advised by your vascular surgeon.
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