Development of a standardized ovine aortic stenosis model: a pathomimetic platform for TAVI evaluation and durability testing.

Background: Transcatheter aortic valve implantation (TAVI) has gained widespread clinical acceptance owing to its minimally invasive approach and enhanced postoperative recovery. This study developed a standardized ovine aortic stenosis (AS) model through surgical implantation of a circular bioengineered annular stent in the aortic root, creating a reproducible pathomimetic platform for TAVI evaluation. Following hemodynamic stabilization, TAVI procedures were performed to systematically assess mid-to-long-term valve functionality and calcification progression. Methods: AS model was established in 11 sheep using extracorporeal circulation assistance technology. Following hemodynamic stabilization (2-4 weeks), TAVI was performed. The modeled sheep were divided into two groups to monitor valve conditions at 3 months ( Results: Successful AS model establishment was achieved in all 11 sheep, with significant increases in mean transvalvular pressure gradient (Δ+17.98 ± 12.71 mmHg) and peak flow velocity observed post-modeling (Δ+ 2.23 ± 0.38 m/s). Post-TAVI evaluation demonstrated progressive hemodynamic normalization, achieving pre-modeling levels (1.72 vs. 6.91 mmHg, Conclusions: The surgically induced ovine AS model effectively replicates clinically relevant hemodynamic perturbations while maintaining excellent procedural feasibility. TAVI in this model achieves complete hemodynamic normalization without accelerating bioprosthetic valve degeneration or calcification. This standardized preclinical platform enables rigorous evaluation of TAVI device performance and durability, providing robust scientific validation for translational applications.