Morphologic performance analysis of the Relay nonbare stent graft in dissected thoracic aorta

Abstract

ObjectiveThe aim of this study was to evaluate morphologic changes in dissected aortas after thoracic endovascular aortic repair (TEVAR) with the use of the Relay Nonbare stent graft stent graft by focusing on the geometric stent graft's performance in remodeling aortas. MethodsWe conducted a retrospective three-dimensional computed tomography analysis preoperatively, postoperatively, and 6 months after TEVAR in patients with residual dissection after type A and those with acute and chronic type B dissections at two German centers. ResultsThirty-nine acute and 54 chronic aortic dissections were included. Median follow-up was 200 (interquartile range, 109-617) days. TEVAR induced aortic remodeling in both groups. Complete false lumen thrombosis along the stent graft (postoperative, 73%; follow-up, 84%; P < .0001) led to a decrease in aortic diameter at the middle stent graft level (preoperative, 45.9 mm [38.6-56.6] vs follow-up, 43.6 [37.4-52.4] mm; P = .009). True lumen expansion was observed in both groups and peaked in acute dissections in the distal landing zone (acute, +9.3 mm vs chronic, +5.8 mm; P < .0001). Migration was 2 (0-5) mm, and bird-beak and endoleak type IA rates were 20% and 4%, respectively. There was no retrograde type A dissection. Distal stent graft-induced new entry occurred in 15%; the major risk factor for incidence was the stent graft's wedge apposition angle (odds ratio, 1.365 [confidence interval, 1.115-1.671]; P = .003). ConclusionsTEVAR with the use of the Relay NBS promotes aortic remodeling in acute and chronic dissections, entailing a low risk of migration, type IA endoleaks, and retrograde type A dissections. Wedge apposition was the predominant risk factor for distal stent graft-induced new entry.