4:12 PM Abstract No. 59 Randomized controlled study of an absorbable vena cava filter in a porcine model

Abstract

To evaluate the long-term safety and efficacy of an absorbable vena cava filter compared to a benchmark IVC filter in a swine model. A randomized controlled GLP study approved by an institutional animal care and use committee was performed with test and control cohorts of Domestic Yorkshire cross swine; 16 were implanted with an absorbable IVC filter (Adient Medical), while 8 were implanted with a Celect IVC filter (Cook Medical) respectively. All animals underwent fluoroscopic imaging consisting of pulmonary angiography and cavography pre- and post-deployment, 5 and 32 weeks. Terminal procedures and necropsy were performed at 32 weeks for all animals. The IVC, heart, lungs, liver, and kidneys were harvested at necropsy. All animals, with exception of one early death due to a recurring hemorrhage at the femoral access site (unrelated to the test device), remained clinically healthy throughout the duration with no major health issues. A summary of the endpoint results is given in the table, revealing that both test and control devices were equally effective in preventing PE; however, the absorbable filter proved safer by avoiding caval perforation and thrombus. The control filter routinely perforated the IVC and produced occasional collateral trauma to adjacent tissues (psoas muscle and aorta). The veins implanted with the absorbable filter were macroscopically indistinguishable from normal adjacent veins at 32 weeks (except for the presence of the radiopaque markers). Non-target tissues showed no device related changes. Implantation of the absorbable IVC filter in swine proved safe and effective, resulting in complete to near complete resorption of the filter polymer in 32 weeks with restoration of the normal appearance and structural properties of the IVC.Tabled 1Randomized Controlled Study ResultsEndpointTest Device (n = 15)Control Device (n = 8)Adient Absorbable IVC FilterCook Celect IVC FilterPulmonary embolism0%0%Filter migration (5 wk)3-8 mm6-20 mmIVC perforation0%100%Perforation grade06 grade II, 2 grade IVIVC thrombus0%75%IVC stenosis (mild)13%25% Open table in a new tab