Intimo-Intimal Intussusception during Endovascular Repair of Type B Aortic Dissection

Stent graft induced aortic intimo-intimal intussusception (SAoII) during thoracic endovascular aortic repair (TEVAR) of type B aortic dissection (TBAD) is a rare complication. This study aimed to report reliable imaging features of SAoII to avoid such a potentially catastrophic event. This retrospective, multicentre observational analysis was registered as a Chinese Clinical Trial (ChiCTR2300073780).

Patients undergoing TEVAR for TBAD in three centres were reviewed from January 2014 to December 2022. SAoII was defined as intra-procedural partial or circumferential disruption of the aortic intima because of TEVAR, excluding those created by natural disease progression. The imaging features and management of SAoII were summarised.

1 643 patients undergoing TEVAR for TBAD were reviewed. Among them, SAoII was observed in 20 patients (mean age, 44.5 ± 11.8 years; 16 men). TEVAR was performed in the acute phase (8 of 20), subacute phase (11 of 20), or chronic phase (1 of 20). Imaging features including displacement of the intima, wire, or delivery system were observed in eight (40%), floating endograft in 17 (85%), intussusception of the intima layer in 13 (65%), true lumen occlusions and visceral artery loss in three (15%), and a single lumen without intimal septa in three (15%) patients. SAoII was observed in 60% (12 of 20) after deployment of the stent graft, in 20% (4 of 20) after introduction of a stent graft delivery system, and in 20% (4 of 20) after the introduction of a super stiff wire. All patients who developed SAoII were endovascularly managed by an additional stent graft; no aortic related death was observed among these patients with SAoII during the median follow up of 51.5 months.

SAoII is a rare but potentially fatal iatrogenic complication during or after TEVAR; endovascular interventions could be effective to manage this acute complication. Timely and accurate identification of decisive imaging features are key to successful treatment.