In some instances, EVAR can result in endoleaks, which represent continued pressurization of the sac (see the image below). Aneurysm sacs may also demonstrate elevated pressure despite the absence of a demonstrable endoleak. This phenomenon has been referred to as endotension.
Angiography is used to diagnose renal area. In this instance, endoleak represented continued pressurization of sac.
Persistently elevated aneurysm sac pressure, whether secondary to endoleak or to endotension, is worrisome because it may progress to AAA expansion and rupture. Early data demonstrated a need for secondary interventions, via endovascular techniques, in as many as 30% of patients over a 6-year period, compared with 10% over a comparable period for open repair. Improvement has been made in the rate of secondary interventions after EVAR, but long-term durability has yet to be determined.
Endoleaks can be classified into four different types, as follows [39] :
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Type I - Blood flow into the aneurysm sac due to incomplete seal or ineffective seal at the end of the graft; this type of endoleak usually occurs in the early course of treatment but may also occur later
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Type II - Blood flow into the aneurysm sac due to backflow from collateral vessels (eg, lumbar or inferior mesenteric arteries)
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Type III - Blood flow into the aneurysm sac due to inadequate or ineffective sealing of overlapping graft joints or rupture of the graft fabric; again, this type of endoleak usually occurs early after treatment, as a consequence of technical problems, or later, as a result of device breakdown
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Type IV - Blood flow into the aneurysm sac due to the porosity of the graft fabric itself, causing blood to pass through from the graft and into the aneurysm sac
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Radiograph shows calcification of abdominal aorta. Left wall is clearly depicted and appears aneurysmal; however, right wall overlies spine.
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On radiography, lateral view clearly shows calcification of both walls of abdominal aortic aneurysm, allowing diagnosis to be made with certainty.
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CT demonstrates abdominal aortic aneurysm (AAA). Aneurysm was noted during workup for back pain, and CT was ordered after AAA was identified on radiography. No evidence of rupture is seen.
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Arteriography demonstrates infrarenal abdominal aortic aneurysm. This arteriogram was obtained in preparation for endovascular repair of aneurysm.
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Lateral arteriogram demonstrates infrarenal abdominal aortic aneurysm. Demonstration of superior mesenteric artery, inferior mesenteric artery, and celiac artery on lateral arteriogram is important for complete evaluation of extent of aneurysm.
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Arteriogram after successful endovascular repair of abdominal aortic aneurysm.
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Ultrasonogram from patient with abdominal aortic aneurysm (AAA). This aneurysm was best visualized on transverse or axial image. Patient underwent conventional AAA repair.
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MRI of 77-year-old man with leg pain believed to be secondary to degenerative disk disease. During evaluation, abdominal aortic aneurysm was discovered.
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Age is risk factor for development of aneurysm.
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Inflammation, thinning of media, and marked loss of elastin.
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Pulsatile abdominal mass.
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Aneurysm with retroperitoneal fibrosis and adhesion of duodenum.
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Aortic endoprosthesis (Cook aortic and aortobi-iliac endograft).
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Endoaneurysmorrhaphy
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Endovascular grafts.
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Atheroemboli from small abdominal aortic aneurysms produce livedo reticularis of feet (ie, blue toe syndrome).
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Enhanced spiral CT scans with multiplanar reconstruction and CT angiogram.
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Angiography is used to diagnose renal area. In this instance, endoleak represented continued pressurization of sac.
