Post-EVAR Endoleaks: A Morphovolumetric Approach to Prediction, Surveillance, and Management

Background/Objectives: To evaluate the association of preoperative morphometric and morphovolumetric parameters with post-endovascular aneurysm repair (EVAR) sac remodeling, endoleak development, and secondary interventions, and to assess the role of volumetric analysis in post-EVAR surveillance. Methods: This retrospective single-center study included 383 patients who underwent elective EVAR for infrarenal abdominal aortic aneurysm between 2016 and 2024, with available pre- and postoperative computed tomography angiography and at least 1 year of follow-up. Diameter- and volume-based sac dynamics were analyzed using standardized morphometric and 3-dimensional morphovolumetric measurements. Endoleak subtype distribution, risk factors, secondary interventions, and survival were assessed using regression and survival analyses. Results: Endoleaks were detected in 26.1% of patients (n = 100), with type II endoleak being the most frequent subtype (12.3%, n = 47), followed by type Ib (6.8%, n = 26), type III (5.5%, n = 21), type Ia (4.2%, n = 16), and 1 patient with type V endoleak in the revised manuscript framework. Secondary interventions were required in 14.1% of patients (n = 54), mainly for type I and III endoleaks, with a mean time to reintervention of 21.7 ± 10 months. Diameter and volume changes were strongly correlated; a 10% increase in aneurysm volume corresponded to an average 4 mm increase in diameter (R² = 0.72, p < 0.001). Significant predictors of overall endoleak included dual antiplatelet therapy, aneurysm length > 133 mm, elevated pre- and postoperative D-dimer levels, aneurysm diameter > 59 mm, aneurysm volume > 164 cm³, and thrombus volume > 89 cm³. Subtype-specific analyses identified distinct risk profiles for type Ia, Ib, II, and III endoleaks. Overall survival did not differ significantly between patients with and without endoleaks (p = 0.227), although worse survival was observed in type Ia and III endoleaks than in type II and Ib endoleaks. Conclusions: Preoperative morphovolumetric parameters are significant predictors of post-EVAR endoleaks and secondary interventions. Volumetric analysis may provide a complementary early signal of aneurysm sac remodeling beyond conventional diameter-based assessment, particularly in patients with type II endoleaks. However, the proposed volumetric thresholds remain exploratory and require prospective external validation before routine clinical adoption. Post-EVAR management should integrate endoleak subtype, sac behavior, and patient-specific morphovolumetric risk factors to improve surveillance and treatment selection.