Abstract
The sandwich endovascular technique is a total endovascular treatment of thoracoabdominal aortic aneurysms (TAAAs) with use of off-the-shelf devices. The technique consists of three steps: (1) deployment of a thoracic stent-graft in a healthy, nonaneurysmal aortic segment of the thoracic aorta; (2) placement of long, self-expanding covered stents in the involved renovisceral vessels; and (3) deployment of abdominal tube endografts between the long, covered stents and the abdominal aorta. The technique offers treatment in urgent setting. The use of the upper extremity and long self-expanding covered stents as chimneys and periscopes after successful cannulation of the renovisceral vessels is mandatory. In this context, knowledge of the design of the used materials and the interaction between them is necessary in order to minimize the risk of persistent gutters which may lead to secondary re-interventions. The published experience is even promising limited and does not allow to draw robust conclusions about the recommended devices to be used.
Keywords
chimney grafts, off-the-shelf devices, periscopes, thoracoabdominal aneurysms, urgent setting
The sandwich endovascular technique is an option for the total endovascular treatment of thoracoabdominal aortic aneurysms (TAAAs). The technique consists of three major steps: (1) deployment of a thoracic stent-graft in a healthy, nonaneurysmal aortic segment of the thoracic aorta; (2) placement of long, self-expanding covered stents in the involved renovisceral vessels; and (3) deployment of abdominal tube endografts between the long, covered stents and the abdominal aorta. This creates the following configuration, from outer to inner side: thoracic device, self-expanding covered stents running from the aortic side branches to the proximal level of the thoracic device (chimney grafts) or to the distal abdominal aorta (periscopes), and lastly, abdominal tube endografts to cover the distal portion of the aneurysm in the abdominal aorta. The three “layers” of endovascular devices in the thoracoabdominal aorta (thoracic endograft > chimney or periscope grafts > abdominal tubes) create the term sandwich technique, or wrap technique.
Procedure
Case Presentation
The patient presented with a contained, ruptured aneurysm from a type Ia endoleak after fenestrated endovascular repair; originally performed in 2005 using a device with two fenestrations. In 2009 the patient underwent reintervention with placement of balloon-expandable covered stents in both renal arteries as a result of fracture of the right balloon-expandable bare-metal stent, which was primarily deployed. At this time the patient had an endoleak from the right renal artery, with significant expansion of the aneurysm sac. Seven years later, the patient presented with a contained rupture. Fig. 13.1 shows the new onset of type Ia endoleak based on computed tomography angiography (CTA).
The cause for the type Ia endoleak was fracture at the origin of the fenestrations ( Fig. 13.2 ).
Procedural Steps
1
Exposure of left axillary artery
The axillary artery was exposed through an incision in the deltopectoral groove. The pectoralis major muscle was divided in the direction of its fibers, as was the pectoralis minor muscle from its the insertion on the coracoid process.
2
Percutaneous transfemoral access
Percutaneous transfemoral access was achieved, using the Prostar XL device (Abbott) in a “preclose” technique. Stiff guidewires were advanced into the aorta, as in standard thoracic endovascular aortic repair (TEVAR).
3
Deployment of thoracic endograft
Thoracic endografts are chosen, as available at the center, including a stainless steel or nitinol endoskeleton. In this case the lower end of the graft was positioned as close as possible to the origin of the celiac trunk ( Fig. 13.3 ).
4
Placement of infrarenal aortic stent-graft
This step involves placement of a bifurcated infrarenal aortic stent graft, cannulation of the contralateral iliac limb, and deployment of the iliac graft. In the event of a distal nonaneurysmal landing zone more than 2 cm in length, deployment of an aortic tube is preferred.
In this case the infrarenal aortic stent-graft is the fenestrated endograft.
5
Cannulation of renovisceral vessels
Cannulation of Visceral Arteries
Puncture of the left axillary artery is performed, or bilateral transbrachial cannulation from the upper extremities (antecubital level). After the double puncture of the left axillary artery, with 1 to 2 cm between the punctures, two short 5-French (5F) sheaths are advanced ( Fig. 13.4 ).
