Aortic Bifurcation Morphology Alone is Not Able to Predict Outcome in Patients Submitted to Elective Endovascular Abdominal Aortic Aneurysm Repair.

PURPOSE: The aim of the present study was to evaluate the impact of the aortic bifurcation (AB) morphological characteristics, analyzed on computed tomography angiography (CTA), on outcomes of patients with abdominal aortic aneurysms (AAAs), treated by endovascular aneurysm repair (EVAR) in a single-center experience.

MATERIALS AND METHODS: A retrospective analysis was conducted using a prospectively collected database. Morphological features considered as potentially impacting outcomes were maximum AB diameter (ABmax ), minimum diameter (ABmin ), mean diameter (ABaverage ), AB area (ABarea ), and AB calcification (ABcalcification ) and thrombosis (ABthrombosis ). Outcome measures were perioperative, 30-day, and midterm AAA-related reinterventions and all-cause mortalities.

RESULTS: Investigators reviewed 306 preoperative CTA scans. Maximum aortic diameter was 51.4 ± 12.4 mm (range 40-110), and mean ABmax was 24.2 ± 8.8 mm (range 10-60), ABmin 17.0 ± 5.4 mm (range 4-40), ABaverage 20.6 ± 6.5 mm (range 9-47.5), and ABarea 35.2 ± 24.2 mm2 (range 6-176). ABcalcification ≥ 50% was present in 63 patients (20.6%), and ABthrombosis ≥ 50% in 102 patients (33.3%). Technical success was obtained in all cases, without perioperative reintervention or death. At 30-day follow-up, the reintervention rate was 3.3%, and mortality rate was 1.3%. At a mean follow-up period of 35 ± 28.6 (range, 1-72) months, reintervention and mortality rates were 6.5 and 4.9%, respectively. None of the analyzed thresholds were predictive of adverse outcomes. At multivariate analysis, association of a narrowed AB with severe calcification of the distal aorta showed a significant differences in terms of reinterventions (p = 0.009).

CONCLUSIONS: Our limited experience seems to reveal that a cutoff of ≤ 20 mm for AB diameter, as in current guidelines, is ineffective in predicting outcomes after EVAR.