Endovascular Salvage After False Lumen Misdeployment of Thoracic Endovascular Aortic Repair or the Frozen Elephant Trunk in Aortic Dissection: A Case Report of Two Patients.

Thoracic endovascular aortic repair (TEVAR) and the frozen elephant trunk (FET) are well-established treatment options for aortic dissection (AD). Inadvertent misdeployment of a TEVAR stent graft or FET into the false lumen (FL) can lead to serious complications. We report two cases of FL misdeployment. First, a 68-year-old female with acute Stanford type B AD underwent TEVAR; follow-up computed tomography angiography (CTA) revealed stent-graft misdeployment into the FL. Second, a 44-year-old female with Marfan syndrome, who had undergone supracoronary ascending aortic grafting for type A AD at 25 years of age, underwent urgent FET 19 years later for a symptomatic dissecting arch aneurysm; follow-up CTA confirmed misdeployment into the FL. In both cases, endovascular rescue was performed with fenestration of the intimal flap and additional stent-graft deployment to reroute flow into the true lumen. Misdeployment of TEVAR or FET into the FL is catastrophic but treatable with rapid diagnosis and timely intervention.