Volume Change after Endovascular Treatment of Common Iliac Arteries ≥ 17 mm Diameter: Assessment of Type 1b Endoleak Risk Factors

Objective: The aim of this study was to assess the post-operative volumetric evolution of common iliac arteries (CIA) ≥ 17 mm diameter with respect to the type of endovascular technique performed and to assess type 1b endoleak risk factors. Methods: All consecutive patients presenting with aneurysmal disease with CIA ≥17 mm treated endovascularly from 2008 to 2016 were included. Patients were divided into two groups dependent upon the type of endovascular technique performed: bell bottom technique (BBT group), vs. other techniques (non-BBT group). Volumetric evolution of the CIA was assessed for each patient by computed tomography angiographic reconstructions performed pre-operatively, at six months, one year, and two years. Multivariable analysis was performed to identify risk factors for type 1b endoleak. Results: From 2008 to 2016, 74 patients with 110 CIA ≥17 mm were treated (BBT group: n = 58; non-BBT group: n = 52). Mean follow up was 48.1 months (median 39.0, IQR 38.1). Mean volumetric evolution significantly differed in the BBT group +14.2% (median 19.9%, IQR 24.6) compared with the non-BBT group: −20.9% (median −20.1%, IQR −26.0), p < .001. The five year type 1b endoleak related re-intervention rate was 16.1% and 7.7% in the BBT and non-BBT groups, respectively (p = .04), mean time to type 1b endoleak was 24.8 months and 54.3 months, respectively. The BBT appeared as a risk factor for type 1b endoleak (OR: 7.13; 95% CI: 1.58–3.04; p < .001). Conclusion: The BBT is associated with an increase in CIA volume post-operatively and consequently can be considered a risk factor for type 1b endoleak. It might be avoided if an iliac branched endograft is possible.