IN-VIVO EVALUATION OF A RETRIEVABLE VENA-CAVA FILTER - THE DIBIE-MUSSET FILTER - EXPERIMENTAL RESULTS

Purpose: To evaluate, in an animal model, the efficacy and safety of a 7 Fr percutaneous vena cava filter for temporary or permanent use. Me thods: The Dibie-Musset (DM) filter is a wire preformed into a double- spiral shape with a spring effect. The experiment was performed in 15 adult sheep and consisted of the insertion of 45 filters, clot trappin g tests, and filter retrieval. Follow-up in all sheep consisted of rad iologic (abdominal radiograph, inferior vena cavogram, abdominal compu ted tomography), macroscopic, and microscopic examinations between day s 8 and 386 after filter placement. Results: Of the 45 filters implant ed in 15 sheep, 29 were retrieved between day 0 and day 15. Filtration efficiency was 100% for clots 4 x 4 x 20 mm. No longterm (1 year) sid e-effects were detectable, Microscopic examination of the vein wall sh owed only a dense intimal fibrosis without signs of acute inflammation at 1 year. Conclusion: These results support the efficiency and safet y of the DM filter in an animal model.