Inner Branched Endovascular Repair of a Post-Type B Dissection Aneurysm Previously Treated With a Nellix in Both Lumens: Making the Most of a Complex Situation.

Introduction: Treatment of chronic type B aortic dissection associated aneurysms where key vessels originate from both the true and false lumens is technically challenging. Further aneurysm formation may require new interventions after initial treatment. Innovative endovascular techniques can lead to successful treatment. Report: A 74 year old man with a type B dissection was treated with an urgent femorofemoral crossover bypass (in 2001) and surgical graft in the thoracic aorta (in 2003). Due to the combination of a chronic type B dissection and a right sided common iliac artery aneurysm, he was subsequently treated with two separate Nellix endoprotheses (Endologix Inc., Irvine, CA, USA) in the infrarenal aorta. The Nellix endoprotheses were deployed in the true and the false lumens (in 2015). Eight years later, he required another intervention due of progressive enlargement of the thoracic aorta between the surgical graft and Nellix endoprotheses. The chosen treatment was a customised two inner branch thoracic endovascular aortic repair (TEVAR) and four inner branch endovascular aortic repairs, in combination with long Viabahn stent grafts from the TEVAR to the old Nellix endoprothesis in the false lumen (in 2021). All stent grafts were patent at three years of follow up. Discussion: This case report presents a patient in whom former techniques were used as an initial treatment for a chronic type B dissection with aneurysm formation complicating further treatment. This report highlights what can be achieved with careful planning in combination with new available devices, resulting in a good individual outcome.