Mechanical Behavior of Valve Stents in Diverse Bicuspid Aortic Valves: Influence of Structural Design and Annular Eccentricity.

OBJECTIVE

To evaluate the expansion mechanics of transcatheter heart valves in bicuspid aortic valve (BAV)anatomies, quantifying the infl uence of stent design and annular eccentricity.

METHODS

Finite element simulations were performed to compare two self-expanding (E, V) and one balloon-expandable (S) stent across four BAV morphologies (Type 0, LR, LN, RN) with varying annular eccentricity (0.2-0.4).Key metrics included post-implant stent ellipticity, stent stress, and aortic wall stress.

RESULTS

The eccentricity of the valve stent after implantation increased with the increase of the eccentricity of theBAV valve ring. Among the four BAV types, the balloon-expandable stent (S-stent) showed higher stent stress andaortic wall stress than the self-expanding stent, but its expansion uniformity was the best. The analysis reveals afundamental trade-off between achieving optimal expansion uniformity and minimizing implant-induced stress.

CONCLUSION

This study provides a biomechanical framework for personalized stent selection in BAV-TAVR, indicatingthat the choice of the optimal device depends on the priority given to specifi c clinical outcomes (such as sealingvs.long-term durability).