\'Sandwich technique\' during EVAR for preserving hypogastric artery: description of a case

Clinical History

Male, 80-year-old patient. A screening US revealed an AAA which increased in size in follow-up until 5.5 cm. The patient was a heavy smoker with multiple comorbidities (chronic obstructive broncopnemopathy) and for this reason was scheduled for an EVAR treatment of his AAA.

Imaging Findings

Pretreatment CT confirmed a 5.5 cm AAA arising below the renal arteries and a right common iliac artery aneurysm extending to the origin of the hypogastric artery (Fig.1a). In order to preserve this vessel EVAR treatment was modified and after surgical preparation of both common femoral arteries also left axillary artery was surgically exposed. After stent-graft deployment (Endurant-Medtronic), through the axillary access a 4F diagnostic catheter was advanced in the right common iliac and hypogastric artery (Fig.1b). After positioning of a stiff exchange wire (Amplatz Superstiff) a covered stent-graft (Fluency-Bard 12x100) was advanced partially inside the hypogastric artery and partially in the common iliac artery. From below an extension cuff (Endurant Medtronic) was positioned between common and external iliac artery. The deployment of both stent-graft was done simultaneously and was followed by a kissing balloon dilatation (Fig.1c, d). Final check and 1 month CT follow-up were regular (Fig. 2).

Discussion

AAA involving one or both iliac arteries and the origin of hypogastric arteries or isolated iliac aneurysms associated to AAA represent a problem for EVAR because they can be a cause of retrograde filling of the aneurysmatic sac through the ipsilateral hypogastric artery. To prevent this event different options have been proposed: embolisation of the origin of the hypogastric artery with coils or plugs [1] is the most frequent option used, however, some complications due to this procedure are reported in 10-30% of cases (buttom ischaemia or visceral ischaemia). Options to avoid these complications are surgical bypass to hypogastric artery from the external iliac artery or the use of branched stent-grafts [2]. The use of fenestrated branched stent-grafts for renal and visceral arteries and precerebral vessels was described since 2008 by Malina et al [3]. First experiences were mainly carried out with "custom made" stent-grafts which are costly, not easily available and complex to deploy. However on the basis of the encouraging results with the "chimney" or "snorkel" technique proposed for preservation of renal arteries arising in short neck AAA using commercially available stent or covered stent during EVAR [4], recently a similar technique has been proposed to preserve patency of hypogastric arteries during EVAR. In two recent papers this technique was defined "Sandwich technique" [5, 6]. The alternative "chimney" or "sandwich" technique requires only commercially available stent-grafts and covered stents which are easily available and quite frequently used. The absence of fenestration in the stent graft avoids complex manoeuvres of positioning and catheterisation of the vessels to preserve. It must be emphasised that two stents have to be oversized in order to avoid flow around them and reperfusion of the sac. While another author [5] suggests the brachial access we preferred the axillary access because this artery has larger diameter and supports sheaths of higher calibre and in the case shown here the 12 mm covered stent deployed in the hypogastric artery needs a 9 Fr sheath.

Differential Diagnosis List

Final Diagnosis

Sandwich technique for hypogastric artery during EVAR treatment

URL:	https://www.eurorad.org/case/9605
DOI:	10.1594/EURORAD/CASE.9605
ISSN:	1563-4086