What does anatomically eligible mean in contemporary thoracic endovascular aneurysm repair for type B aortic dissection?

Modern management of type B aortic dissection (TBAD) in some cases necessitate treatment by thoracic endovascular repair (TEVAR). Some patients are not anatomically eligible for simple, standard TEVAR, since critical side branches of the aorta would be covered by the stent graft and might require revascularisation. This commentary will outline some strategies for complex thoracic aortic repair in the aortic arch that could be considered in patients with dissection anatomy that does not allow for stand-alone TEVAR. Current guidelines provide vague guidance in assessment of anatomic eligibility for TEVAR. The principles of these adjunctive repair strategies - debranching of the supraaortic vessels, parallel grafts, physician-modified endografts and in-situ fenestrations - and short-term outcomes from a selection of larger studies (of >40 patients) are presented. The literature is somewhat heterogenous regarding patient selection and intervention strategy. Still, collectively, there seems to be a trend towards decreased morbidity and mortality, along with good technical outcomes, with newer strategies including dedicated TEVAR devices alone or in combination with physician-modification and/or in situ fenestration compared to conventional debranching and parallel grafting.