503 - Prognostic Factors Following Embolization in Persistent Type II Endoleaks After Endovascular Aneurysm Repair (EVAR)

Purpose: Persistent type II Endoleaks after endovascular aneurysm repair (EVAR) are commonly managed with embolization, but predictors of sac response and endoleak resolution remain poorly defined.^1,2 Evaluation of arterial and venous volumetric and integral total flow within the sac may serve as prognostic factors following embolization.

Materials and Methods: We retrospectively reviewed 30 patients who underwent embolization for type II Endoleaks using the translumbar approach. Aneurysmal sac behavior was categorized as decreased, stable, or increased diameter on follow-up imaging 6 months post-embolization. Clinical variables, sac area, arterial and venous volumes, and arterial and venous integrals were collected using MIM v.6.9.4 (MIM Software, Cleveland, Ohio). Logistic regression and receiver operating characteristic (ROC) analysis were used to assess associations with endoleak resolution using R.

Results: The average age of our cohort was 71 years, with 20% female. 6 patients (20%) had undergone a prior embolization attempt. N-butyl cyanoacrylate glue was the most used embolic used (40%). ROC analysis demonstrated fair discrimination for aneurysmal sac enlargement (AUC 0.71–0.74), with optimal cutoffs of arterial volume >3.6 mL (sensitivity 88%, specificity 64%) and arterial integral total >400 HU·mL (sensitivity 75%, specificity 77%). Kruskal–Wallis testing confirmed a significant association for arterial integral total (p = 0.041), whereas venous parameters did not reach statistical significance. Other clinical parameters, including age, sex, hypertension, anticoagulant use, coronary artery disease, tobacco history, diabetes, and hyperlipidemia, were not significant predictors of aneurysmal sac behavior or resolution of the endoleak.

Conclusion: In this cohort, arterial volumetric parameters showed moderate ability to predict aneurysmal sac behavior after embolization of type II endoleaks. Patients with larger volume arterial flow in the aneurysm sac on CTA imaging may experience the best clinical results from a translumbar approach.