Predictors of type IIIa endoleak after endovascular aortic repair with anatomic fixation endografts

Objective: Concern regarding the use of anatomic fixation endografts was raised, as previous data suggested increased risk of late device uncoupling and type IIIa endoleak (EL) in this setting. Some risk factors have been identified as predictors of graft failure. We aim to determine if increase in aortic tortuosity index (TI) over the time is associated with an increased risk of type IIIa EL. Methods: We conducted a single-center retrospective cohort study of patients treated with endovascular repair of infrarenal abdominal aortic aneurysms with the Endologix platform. Patients with at least two postoperative computed tomography (CT) scans were included in the analysis. Aortic TI was determined in the first and last available CT scan to determine any change. Multivariate analysis was performed to detect risk predictors of type IIIa EL occurrence. Results: A total of 173 patients were included in the analysis. Twenty-one patients (12.1%) presented with type IIIa EL. Cumulative freedom from type IIIa EL determined by Kaplan-Meier method was 99.4%, 92.5%, 86.1%, and 83.3% at 1, 3, 5, and 8 years, respectively. Time-dependent optimal cutoff values of 0.03 for aortic TI increase and 15 mm for decrease in modules overlapping over time were obtained with the Contal and O'Quigley method to predict type IIIa EL. After dichotomizing data around these critical values, a Cox proportional hazards model was obtained to predict type IIIa EL occurrence. Maximum preoperative abdominal aortic aneurysm diameter (odds ratio [OR], 1.09), smoking (OR, 26.67), initial device components overlap (DCO) (OR, 0.91), aortic TI increase >0.03 (OR, 4.56), and decrease in DCO >15 mm (OR, 6.13) were associated with type IIIa EL occurrence. Conclusions: Aortic TI increase, DCO decrease, maximum preoperative aortic diameter, tobacco use, and initial DCO were predictive of type IIIa EL occurrence. Close follow-up with CT scan with aortic TI and device components overlap measure is warranted in these patients, and prompt repair seems justified when any of these risk factors is present.