Characterization of Aortic Degeneration and Inflammatory Profiles in Porcine Models of Abdominal Aortic Aneurysm

Purpose: Abdominal aortic aneurysm (AAA) is a progressive vascular disease associated with high morbidity and mortality. Translational imaging and interventional research are limited by the availability of standardized large-animal models. This exploratory study compared different endovascular and pharmacological strategies for AAA induction in swine and characterized associated morphological and inflammatory vessel wall changes.

Materials and methods: 19 female German Landrace swine were enrolled, with 18 included in the final analysis (n = 3 per group). Animals were assigned to five intervention groups and one untreated control group. Interventions comprised combinations of mechanical aortic dilation, intra-aortic administration of collagenase (6,000 IU), Elastase (500 IU), calcium chloride (CaCl₂, 25%; group-specific dosing), and oral β-aminopropionitrile (BAPN; 0.05-0.15 mg/kg). Aortic diameter changes and molecular markers of inflammation and vascular remodeling were assessed. Given the limited group size, analyses were considered exploratory and hypothesis-generating.

Results: Mechanical dilation combined with enzymatic and CaCl₂ exposure resulted in the largest mean increase in aortic diameter (1.63 ± 0.25 cm vs. 0.61 ± 0.04 cm in controls). This group was associated with increased Galectin-3 expression (89.69 ± 7.02%). BAPN alone was associated with smaller aortic dilations (0.73 ± 0.06 cm) and marked reduction of vascular smooth muscle cell markers, including α-smooth muscle actin (23.50 ± 4.82%), consistent with active extracellular matrix remodeling.

Conclusion: Within this exploratory large-animal setting, combined mechanical and enzymatic injury was associated with more pronounced structural remodeling compared to isolated approaches, whereas BAPN predominantly induces early vessel wall degeneration. The graded phenotypes observed across groups provide a comparative framework for future preclinical imaging-based and interventional AAA research.

Key points: · The porcine models enable comparative preclinical investigation of graded abdominal aortic aneurysm phenotypes.. · Combined mechanical dilation and enzymatic injury is associated with more pronounced structural remodeling in swine.. · Greater structural remodeling is accompanied by increased macrophage-associated inflammatory markers.. · Vascular smooth muscle cell markers are reduced in association with vessel wall degeneration..

Citation format: · Ranner-Hafferl M-LHH, Mangarova DB, Heyl JL et al. Characterization of Aortic Degeneration and Inflammatory Profiles in Porcine Models of Abdominal Aortic Aneurysm. Rofo 2026; 10.1055/a-2854-8724.