Techniques for supra-aortic trunk preservation in thoracic endovascular aneurysm repair

Stent graft placement for aneurysmal disease of the aortic arch and proximal descending aorta is limited by the need to preserve flow to the supra-aortic trunks. Whilst extra-anatomical bypass and procedures combining open and endovascular arch repair are currently used in this setting, less invasive totally endovascular solutions have been described. These include in-situ fenestration of a thoracic stent graft using a retrograde approach from the target vessel to the lumen of the main device, to which it is connected by a smaller covered stent. Alternatively, so-called 'chimney' stents have been used, placing a parallel stent alongside the main device, connecting the aortic branch vessel with the native aortic lumen proximal to the seal zone of the main thoracic device. We review these techniques and discuss the merits and potential disadvantages of each procedure.