OBJECTIVE: Aortic geometry has been shown to influence the development of endograft malapposition (bird-beaking) in thoracic endovascular aortic repair (TEVAR), but the extent of this relationship lacks clarity. The aim of this study was to develop a reproducible method of measuring bird-beak severity and to investigate preoperative geometry associated with bird-beaking.METHODS: The study retrospectively analyzed 20 patients with thoracic aortic aneurysms or type B dissections treated with TEVAR. Computed tomography scans were used to construct three-dimensional geometric models of the preoperative and postoperative aorta and endograft. Postoperative bird-beaking was quantified with length, height, and angle; categorized into a bird-beak group (BBG; n= 10) and no bird-beak group (NBBG; n= 10) using bird-beak height =5mm as a threshold; and correlated to preoperative metrics including aortic cross-sectional area, inner curvature, diameter, and inner curvature*diameter as well as graft diameter and oversizing at the proximal landing zone.RESULTS: Aortic area (1002± 118mm2 vs 834± 248mm2), inner curvature (0.040± 0.014mm-1 vs 0.031± 0.012mm-1), and diameter (35.7± 2.1mm vs 32.2± 4.9mm) were not significantly different between BBG and NBBG; however, inner curvature*diameter was significantly higher in BBG (1.4± 0.5 vs 1.0± 0.3; P= .030). Inner curvature and curvature*diameter were significantly correlated with bird-beak height (R= 0.462, P= .041; R= 0.592, P= .006) and bird-beak angle (R= 0.680, P< .001; R= 0.712, P< .001).CONCLUSIONS: TEVAR bird-beak severity can be quantified and predicted with geometric modeling techniques, and the combination of high preoperative aortic inner curvature and diameter increases the risk for development of TEVAR bird-beaking.
View details for DOI 10.1016/j.jvs.2019.11.045
View details for PubMedID 32035770