3:36 PM Abstract No. 277 First-in-human evaluation of an absorbable vena cava filter for the prevention of pulmonary embolism

Abstract

To prospectively evaluate an absorbable vena cava filter for short-term protection from pulmonary embolism in humans for the first time. This was a prospective, single-site, single-arm clinical trial of 8 subjects with temporary risk of DVT and/or PE conducted at Hospital Universitario, Monterrey, Mexico under Institutional Review Board (IRB) and COFEPRIS approval. The primary objective was to evaluate the safety of the first absorbable IVC filter in a limited number of humans. Absorbable filters (Adient Medical, Pearland TX) were placed prophylactically in 7 subjects prior to major orthopedic (5) and gynecological (2) surgeries, while one was placed following a DVT. The mean Caprini VTE risk score was 7.8 ± 1.8, all within the highest DVT risk category (≥ 5). All subjects underwent computerized tomography (CT) cavography and abdominal radiography prefilter, 5, 11, and 36 weeks following filter placement to assess filter migration, embolization, perforation, and caval thrombosis and stenosis. PE was assessed prefilter and 5 weeks following filter placement via CT angiography. No pulmonary embolism was symptomatically reported throughout the study or detected at the planned 5 week assessment. No filter migration was detected throughout the study based on the fixed location of the cylindrical radiopaque markers (located at the filter apex) relative to the vertebral bodies at the follow-up visits. No filter embolization or perforation was detected, and no stenosis was observed at the follow-up visits. A thrombus measuring approximately 7-mm diameter x 20 mm long was observed shortly after deployment in the filter basket of the therapeutic subject with DVT history. Such thrombus was not apparent in the filter basket at the subsequent 5-week follow-up, nor was a PE detected. Overall throughout the study, no filter-related adverse events were reported. Non–filter-related adverse events included mild influenza and septic arthritis prior to a planned total knee arthroplasty. Implantation of an absorbable vena cava filter proved safe in a limited number of human subjects. No pulmonary embolism or filter-related adverse events were observed.