Preliminary investigation of the Irie inferior vena caval filter

PURPOSE: In vitro and in vivo investigations were performed to evaluate the Irie retrievable inferior vena caval (IVC) filter. MATERIALS AND METHODS: The clot capturing performance of the Irie and five other IVC filters was assessed in both horizontal and vertical orientations within a pulsed-flow circuit with 240 clot challenges for each filter. Subjective comparisons of the flow disturbance characteristics of the Irie and three other filters were also performed. In vivo studies consisted of 13 Irie filter insertions and eight attempted retrievals in 11 pigs. Histologic evaluation of the IVC was performed with the Irie filter in situ and following retrieval. RESULTS: In vitro testing demonstrated the clot capturing capability and flow disturbance characteristics of the Irie filter to be similar to those of other IVC filters. Filter deployment problems occurred during three of the 13 insertions. Six of the eight retrieval procedures were successful; four filters were retrieved 1 month after insertion. Follow-up cavography demonstrated two tilted filters and three caval perforations. CONCLUSION: The performance of the Irie filter is similar to that of other currently available IVC filters. The filter can be retrieved after neointimal incorporation of the struts into the IVC wall.