New recent techniques have been introduced to address these risks by utilizing a segment of the supra-renal portion of the aorta to increase the sealing zone, such as with fenestrated EVAR, chimneys and snorkels. These techniques may be suitable in certain patients with qualifying factors, e.g., configuration of renal arteries, renal function. However, these are more complex procedures than standard EVAR and may be subject to further complications.An approach that directly augments the fixation and sealing between the graft and aorta to mimic the stability of a surgical anastomosis is EndoAnchoring. EndoAnchors are small, helically shaped implants that directly lock the graft to the aortic wall with the goal to prevent complications of the seal, especially in adverse neck anatomies. These EndoAnchors may also be used to treat identified leaks between the graft and proximal neck. Procedure-related
Arterial dissection, contrast-induced kidney failure, thromboembolizaton, ischemic colitis, groin hematoma, wound infection, type II endoleaks, myocardial infarction, congestive heart failure, cardiac arrhythmias, respiratory failure. Device-related
Endograft migration, aneurysm rupture, graft limb stenosis/kinking, type I/III/IV endoleaks, stent graft thrombosis, or infection. Endoleaks
An endoleak is a leak into the aneurysm sac after endovascular repair. Five types of endoleaks exist:
Type I - Perigraft leakage at proximal or distal graft attachment sites (near the renal and iliac arteries)
Type II - Retrograde flow to the aneurysm sac from branches such as the lumbar and inferior mesenteric arteries. Type II endoleaks are the most common, and least serious type of endoleak. Type II endoleaks do not require immediate treatment, as a portion will resolve spontaneously.
Glue: Trans-catheter embolic glue has been used to treat type I endoleaks, with inconsistent success. EndoAnchors: Small, helically shaped devices are screwed through the endograft and into the aortic wall. EndoAnchors have been used successfully to treat endoleaks and, in concert with an aortic extension endograft, to treat migration of the original endograft. Rigorous evaluations and long-term outcomes of this technique are not yet available. Risks
The complications of EVAR can be divided into those that are related to the repair procedure and those related to the endograft device. For example, a myocardial infarction that occurs immediately after the repair is normally related to the procedure and not the device. By contrast, the development of an endoleak from degeneration of endograft fabric would be a device-related complication.Durability and problems such as endoleaks may require careful surveillance and adjuvant procedures to ensure the success of the EVAR or EVAR/hybrid procedure. CT angiography (CTA) imaging has, in particular, made a key contribution to planning, success, durability in this complex area of vascular surgery.A major cause of complications in EVAR is the failure of the seal between the proximal, infra-renal aneurysm neck and the endovascular graft. Risk of this form of failure is especially elevated in adverse or challenging proximal neck anatomies, where this seal could be compromised by unsuitable geometric fit between the graft and vessel wall, as well as instability of the anatomy.