Second-generation percutaneous bioprosthetic valve: a short-term study in sheep

Area of Science:

• Biomedical Engineering
• Vascular Surgery
• Regenerative Medicine

Background:

• Deep chronic venous insufficiency lacks widely accepted treatment options.
• Bioprosthetic venous valves (BVVs) offer a minimally invasive alternative to reconstructive surgery.
• Previous BVV designs occasionally experienced tilting, compromising function.

Purpose of the Study:

• To evaluate the deployment, stability, and short-term function of a second-generation BVV.
• To address the issue of tilting observed in earlier BVV models.
• To assess the efficacy of a novel percutaneously implantable venous valve in an animal model.

Main Methods:

• Second-generation BVVs (double stent or Z-stent designs) were implanted percutaneously into the jugular veins of 24 sheep.
• Deployment and immediate function were assessed via venography.
• Valve stability and function were evaluated at 6 weeks post-implantation, followed by gross pathological examination.

Main Results:

• All 48 implanted BVVs showed no tilting during placement and exhibited good immediate function.
• Angiographic competency at 6 weeks was high for nitinol ZS BVVs (100%) and nitinol DS BVVs (92.3%).
• Dysfunction occurred in 4 valves due to oversizing or intimal hyperplasia, highlighting the importance of precise valve sizing.

Conclusions:

• The second-generation BVV allows for non-tilted placement, essential for proper valve function.
• Exact matching of valve size to vein diameter is critical for successful long-term outcomes.
• These findings support further clinical research for treating deep chronic venous insufficiency with BVVs.