Development and evaluation of a new biodegradable vena cava filter in a canine model

Abstract

Purpose: Preliminary testing of a new biodegradable inferior vena cava filter in a canine model. Methods: The biodegradable filter consisted of two parts, a filter cone and a stent. The filter cone was constructed of six polyglycolic acid polymer strands anchored to a handmade absorbable stent. Central inferior vena cava fixation was accomplished by the absorbable stent, which was made of polycaprolactone. Device insertion was performed through a 9F sheath under ultrasound guidance on 10 adult beagles. The filters were operatively retrieved at 6 weeks after implantation. The inferior venae cavae were subsequently analyzed grossly and using light microscopy. Results: None of the 10 beagles had abnormal vital signs. All of the 10 filters migrated cephalad approximately <2 cm and remained below the renal vein ostia. One specimen had evidence of incorporated residual strands within the caval wall on gross examination. The caval wall became thickened at the level of filter placement without significant lumen narrowing. There was no evidence of pulmonary embolism caused by degradation products of the absorbable strands. Conclusion: Biodegradable inferior vena cava filters are feasible and potentially could be used in specific patients who are at temporary high risk of venous thromboembolism.

Keywords

• biodegradable
• deep venous thrombosis
• pulmonary embolism
• vena cava filter