Is percutaneous implantation of a bovine venous valve in the inferior vena cava a reliable technique to treat chronic venous insufficiency syndrome?

BACKGROUND

To evaluate the feasibility and safety of percutaneous implantation of a balloon-expandable valved stent in the inferior vena cava.

MATERIAL/METHODS: A valve harvested from a bovine jugular vein, preserved in glutaraldehyde and mounted in a stent, was evaluated in animals. Six lambs, weighing 30 to 40 kg, were included in the study. Under general anesthesia, a valved stent with its 18-Fr delivery system was inserted through the right jugular vein, advanced, and delivered in the inferior vena cava. Hemodynamic and angiographic evaluations were performed prior to, immediately after, and two months after implantation.

RESULTS

All valved stents were successfully implanted in the desired position. No early or late migration of the stent was noted in any animal. All valves were perfectly competent at the time of implantation. At 2 months, none of the valves were functional. The inferior vena cava was occluded at the site of valve insertion and collateral circulation was present in all animals. At autopsy, the valved stent was completely occluded.

CONCLUSIONS

Valve implantation is feasible in the venous system through a percutaneous approach. The function of this valve in that position is limited by the absence of a high pressure gradient. Animal models and improvements in the device are mandatory before considering this technique as a reliable procedure to treat chronic venous insufficiency syndrome in humans.