Effect of aortic angulation on the outcomes of fenestrated-branched endovascular aortic repair

Objective: To investigate the effect of aortic angulation on the early and midterm outcomes of fenestrated-branched endovascular aneurysm repair for thoracoabdominal aortic aneurysms (TAAA) or pararenal aortic aneurysms (PRAA). Methods: We retrospectively reviewed the data of consecutive patients enrolled in a prospective nonrandomized physician-sponsored investigational device exemption study (2013-2018). The infrarenal, suprarenal, and supraceliac aortic angles were measured on three-dimensional reconstructions of the preoperative computed tomography angiogram; a 45° cutoff was used for the analysis. Endpoints were technical success, freedom from endograft-related complications (defined by type IA/IB/IIIA/IIIB/IIID endoleaks, and limb thrombosis); and freedom from target vessel instability (defined by branch-related death, occlusion, rupture or reintervention for stenosis, endoleak, or disconnection). Cox proportional hazard multivariable regression analyses were preformed to assess impact of covariates. Results: There were 298 patients treated for 102 PRAAs (34%) and 196 TAAAs (66%) (78 extent IV, 118 extent I-III) with 1156 renal-mesenteric vessels incorporated. An angulation of >45° was present in the infrarenal aortic axis in 94 patients (32%), suprarenal axis in 39 (13%), and supraceliac axis in 93 (31%). A supraceliac angle of >45° was more common with extent I-III TAAAs (P = .01). Technical success was 97% and was not significantly related to aortic angulation; the total operating time and fluoroscopy time were significantly longer in patients with any aortic angulation of >45°. Freedom from endograft-related complications was 93% (95% confidence interval [CI], 90%-97%) at 42 months, and was not associated with infrarenal (HR, 1.0; 95% CI, 0.4-2.9; P = .976), suprarenal (HR, 1.7; 95% CI, 0.5-1.8; P = .428), or supraceliac (HR, 0.9; 95% CI, 0.3-2.6; P = .886) aortic angles of >45°. Overall freedom from target vessel instability was 92% (95% CI, 90%-94%) at 42 months. By multivariable analysis, target vessel instability was not affected by an infrarenal angle of >45° (HR, 1.5; 95% CI, 0.9-2.4; P = .135) and a supraceliac angle of >45° (HR, 0.9; 95% CI, 0.5-1.5; P = .627), but was associated with a suprarenal angle of >45° (HR, 5.6; 95% CI, 3.5-9.1; P < .001), even after adjustment for aneurysm extent and type of bridging stent. In this subgroup of patients, the use of directional branch vs fenestration (P = .10) and the type of bridging stent (P = .10) did not significantly impact target vessel instability. Conclusions: Fenestrated-branched endovascular aneurysm repair can achieve excellent early and midterm results among patients with an aortic angulation of >45°, with no increase in rates of graft-related complications. However, increased aortic angulation was associated with longer operative and fluoroscopy times. The suprarenal aortic angle was the most important determinant of more target vessel events, independent of stent design or which bridging stent was selected.