Type-II endoleak

Rhee SJ, Ohki T, Veith FJ, Kurvers H (2003) Current status of management of type II endoleaks after endovascular repair of abdominal aortic aneurysms. Ann Vase Surg 17 335-344... 

Martin ML, Dolmatch BL, Fry PD, Machan LS (2001) Treatment of type II endoleaks with Onyx. J Vase Interv Radiol 12 629-32... 

A type II endoleak corresponds to the retrograde filling of the aneurysm mainly from lumbar arteries and/or IMA but also in rare situations from sacral, gonadal or accessory renal artery (Figs. 14.3,14.4). 

Type II endoleaks can be associated with aneurysmal expansion and rupture however, this risk is much less than with the type I and III endoleaks (0.5 versus 3.4 %) [9,10]. Aleak in the setting of a shrinking aneurysm can generally be followed, without immediate intervention. It is well established that up to 40 % of type II endoleaks will seal spontaneously. Some have advocated intervening in all endoleaks persisting beyond 3-6 months, while other groups recommended observing leaks in the absence of aneurysm expansion. We favor the last approach. In our experience with biphasic helical CT follow-up of more than 300 patients treated by EVAR from 1994 to 1998, only three patients needed intervention for type II endoleak. 

Fig. 14.7a,b. Diphasic helical CT. a Arterial phase demonstrates no endoleak. b Delayed phase showed a type II endoleak (white arrow)... 

The occlusion of the iliac artery is usually sufficient to treat the leak. However, in cases of long-term type IC endoleak, many outflow vessels may have developed and the leak may communicate with multiple lumbar arteries and the IMA. These enlarged vessels might be source of late type II endoleak. Thus, we usually embolize both the outflow vessels and the sac before occluding the iliac artery. Another attractive technique to achieve the occlusion of the common iliac artery is to perform an endovascular internal to external iliac artery bypass using stentgraft. This technique can allow the exclusion of the common iliac preserving the internal iliac artery. 

Persistent type II endoleaks usually have a complex architecture. They have been compared to the arteriovenous malformation with the sac forming the... 

Regardless of the route chosen, the most important task is to access the channel or the sac. It is critical to disrupt the network between the involved vessels. This is more important than occluding any one vessel or even embolizing the endoleak sac (Figs. 14.3, 14.4). This explains the high rate of recurrence after IMA embolization alone (Fig. 14.4) compared to translumbar embolization for type II endoleak in one report [44]. 

The use of several other agents has been reported with translumbar treatment of type II endoleaks, including Onyx, Ethibloc, thrombin, and Cyanoacrylate [46-50]. 

Schmid R, Gurke L, Aschwanden M, et al (2002) CT-guided percutaneous embolization of a lumbar artery maintaining a Type II endoleak. J Endovasc Ther 9 198-202... 

Ellis PK, Kennedy PT, Collins AJ, Blair PH (2003) The use of direct thrombin injection to treat a Type II endoleak following endovascular repair of abdominal aortic aneurysm. Cardiovasc Intervent Radiol 26 482-484... 

Steinmetz E, Ruhin BG, Sanchez LA, et al (2004) Type II endoleak after endovascular abdominal aortic aneurysm repair a conservative approach with selective intervention is safe and cost-effective. J Vase Surg 39 306-313... 

Occasionally, communications between branches of an uninvolved IIA and distal lumbar arteries can create type-II endoleaks (Fig. 15.1). This can be a more technically challenging situation and embolization of the distal branches should be attempted only if growth of the aneurysm sac has been documented (see Sect. 15.2.1). 

Occasionally, communications between various branches of the IIA and the lumbar arteries may cause retrograde flow into the sac of an aortic aneurysm creating a type-II endoleak. Microcatheter traversal of the entire length of these conununications may not always be possible. Under such circumstances, liquid embolic agents have been employed to occlude the feeder arteries. As mentioned above, this practice may cause ischemic radiculopathy if the targeted vessels are either lateral sacral or iliolumbar arteries. It may be more prudent to coil embo-lize these arteries and use alternative approaches to deal with the possible residual type-II endoleak (see Chap. 14). 

Mertens et al. (2011) looked at the long-term results of patients treated with the Zenith Flex stent graft. They analyzed 143 patients for overall survival, intervention-free survival, aneurysm rupture rates, early and late postoperative complications and endoleaks. At 5 years, 72.1% of patients and at 8 years 50.9% had survived. By 8 years 9% of patients (six total) had experienced a late aneurysm rupture, with three fatalities. Forty-seven patients experienced endoleaks, 18 of which were type 1,25 had one or more type II endoleaks (33 cases in total) and three type III one of these required a conversion to open repair and another required a bypass, indicating a defect in the stent graft material rather than an incomplete seal between the aortic limb stubs and the extensions. There was also one case of endotension and six cases of stent fracture. The authors in this study concluded that the Zenith Flex endograft is an excellent device with good long-term results and low aneurysm-related mortality. 

Australian, British and American surgeons have looked at the intermediate results of the US trial for the fenestrated graft to evaluate the safety and shortterm effectiveness of the device.Thirty patients with short proximal necks were enrolled in the trial and treated with the Cook Zenith custom-fenestrated devices. None of the visceral arteries, renal or superior mesenteric, were lost as a result of the surgery. After 24 months there were no aneurysm-related deaths, ruptures, or conversions to open surgeries. There were 6 incidences of type II endoleak at 12 months and 4 at 24 months. In all patients the diameter... 

Additional clinical applications in the body that can benefit from C-arm CT are drainages and punctures. When performing percutaneous biliary drainage procedures, Froehlich et al. (2000), for example, found that C-arm CT resulted in decreased procedure and fluoroscopy times. C-arm CT can also be beneficial for complicated transjugular intrahepatic portosystemic shunt cases (SzE et al. 2006). Binkert et al. (2006) described another successful application for C-arm devices providing both 2D and 3D imaging. They used the 3D cross-sectional information for needle placement and 2D fluoroscopy to perform embolization of translum-bar type II endoleaks. 

Binkert CA, Alencar H, Singh J, et al. (2006) Translumbar type II endoleak repair using angiographic CT. J Vase Intervent Radiol 17 1349-1353... 

Fig. 23.9. a Type II endoleak after EVAR of an abdominal aortic aneurysm, with a bifurcation graft. The endoleak is filled from a retrograde flow out of a lumbar artery (arrow), b Type III endoleak after EVAR of an abdominal aneurysm. The graft is ruptured (arrowhead), leading to this type of endoleak... 

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