Deployment performance and retrievability of the Cook Celect vena cava filter.

Purpose: To test the safety, performance, and retrievability of the Cook Celect vena cava filter.

Materials And Methods: Twenty female or castrated male sheep were implanted with two Celect filters in series, in the inferior vena cava. The animals were divided into five groups of four animals according to day of filter retrieval. Filter retrieval occurred at approximately 30, 60, 90, 180, and 360 days after implantation. At each time point, two sheep underwent retrieval attempts of both the cranial and caudal filters. These animals were recovered for 30 days, at which time healing was assessed. In two additional sheep at each time point, retrieval of only the cranial filter was attempted and the caudal filter was left in situ. These sheep were euthanized after retrieval, and the segment of vena cava encompassing the sites of both the retrieved filter and the filter left in situ was excised for gross and histopathologic analysis.

Results: Retrieval attempts occurred at 34, 62, 90, 188, and 393 days after implantation. All retrievals were successful (30 of 30). Tilt was detected in eight filters at implantation; six had self-centered before retrieval. At retrieval, no filter migration or deformation was reported. All filters were retrieved with acceptable levels of force. At each time point, there was evidence of mild intimal hyperplasia at the filter anchoring sites and no evidence of vena cava injury.

Conclusions: The Celect vena cava filter was safely used as a retrievable filter for up to 393 days in an ovine model.