To evaluate the safety and performance of the Caterpillar Arterial Embolization Device when used for arterial embolization

A retrospective review of G2 inferior vena cava filter removals was performed in order to identify objective measures indicating that it is more difficult to remove a filter that has been in place for >180 days as compared to one that has been in place <=180 days. All G2 filter implants from September 2005 until December 31, 2007 were reviewed. Filter removal procedures performed up to June 2008 were included in order to allow an adequate opportunity for filter removal. All filter removals were performed by a single operator with prior experience removing the Recovery Filter. Information regarding length of procedure, fluoroscopy time, and contrast use were collected. Information regarding filter migration, filter tilt, filter penetration of the IVC, filter fracture, and caval narrowing were collected from a retrospective review of the images from placement and retrieval procedures. Additional techniques required to remove the filter beyond that described in the device IFU were also recorded. Between September 2005 and December 2007, 391 G2 IVC filters were placed. As of the time of preparation of this manuscript 172 patients presented for G2 filter removal, of which, 168 G2 filters were successfully removed (42.9% overall removal rate, 97.7% success rate). Four filters could not be removed, two due to severe tilt with filter apex endothelialization (days 143 and 218) and two due to asymptomatic caval occlusion. The average duration of filter implantation for those filters eventually removed was 220 days (min 4 days, max 714 days). When grouped by filters with implantation times <=180 days and those >180 days (n=84 in each group), no statistical difference in procedure time, fluoroscopy time and contrast use was identified. Additional maneuvers beyond those called form in the IFU were required in 12 cases, 5 for filters in place >180 days. No filter removal procedure related complications occurred. The removal of a G2 filter that has been in place for longer than 180 days is safe, effective,and requires no significant increase in effort as measured by procedure time, fluoroscopy time, contrast usage, and used of additional removal techniques.