Animal ex-vivo model for the reproduction of the human ascending aorta

Open surgical repair is the gold standard for ascending aortic (AA) diseases, but the need to manage high-risk patients has promoted interest in endovascular alternatives. However, their application in the AA remains limited, in part because suitable experimental models that accurately reproduce human geometry and biomechanics are lacking. We developed and validated a novel ex-vivo porcine model that replicates the human AA by suturing the AA of a first specimen with an additional ascending and arch segment from a second aorta. Twelve models were prepared and tested in a mock circulatory loop under physiological pressure and flow conditions. Geometrical similarity to human anatomy, mechanical behaviour, and in-vitro perfusion feasibility were evaluated by measuring length, diameter, distensibility, and pulse wave velocity (PWV). The procedure extended the native porcine AA + arch from 5.8 ± 0.4 cm to 11.6 ± 1.1 cm, matching the human length (∼12.4 cm), while diameters remained within the physiological human range (27-36 mm). Despite a local restriction at the suture site, distensibility (2.3-2.8 × 10⁻³ mmHg⁻¹) and PWV (3.8 ± 0.6 m/s) values were comparable to native porcine aortas suggesting preserved biomechanics, and differences from typical human values reflected expected interspecies variability rather than model artifacts. The extended porcine AA model accurately reproduces human AA geometry and mechanical response without compromising tissue integrity. The model provides a practical and reproducibleex-vivoplatform forin-vitro testing and development of novel endovascular devices targeting human AA, bridging the gap between bench-top validation and preclinical evaluation.