Abstract No. 350: Changes in tilt angle, position and penetration of inferior vena cava (IVC) wall of ALN, Bard, Cook and Cordis retrievable IVC filters

Abstract

To determine tilt angle, displacement along IVC and extent of filter penetration of IVC wall by retrievable Cook, Bard, Cordis and ALN IVC filters. The imaging data of all consecutive patients who had Cook, Bard, or ALN inferior vena cava (IVC) filter placed between January 2007 and July 2010, were reviewed retrospectively. The choice of IVC filter placed was at the discretion of the operator, and this study was not randomized. Cases were retrieved by audit of the radiology PACS database. Measurements of tilt angle and position were made using measuring tools in the PACS (InteleViewer) at the insertion, and at the removal. Tilt angle was determined by comparing the long axis of the filter and the long axis of the IVC. Positive tilt angles are to the right. Position of the filter was determined by measuring the distance between venous landmark (caudal end of lowest main renal vein) and the superior tip of the filter. Net tilting and displacement along the IVC was calculated by subtraction of measurements from insertion and retrieval venograms. Furthest penetration caval wall by filter leg was estimated by measurements on retrieval vena cavogram. This study was performed at the 2 adult sites of a large urban academic center, one of which is a Level-1 trauma center. All filter types exhibited some changes in tilt angle, migration and wall penetration. Results are presented in the (Table).Tabled 1Change in tilt angle (degrees) (range)Change in filter apex position (cm) (range)Caval wall penetration by filter (cm) (range)ALN (n=25)0.96 (−16.1 – 18.4)0.37 (−3.65 – 6.5)0.32 (0 – 0.85Bard Recovery & G2 (n=24)4.35 (−7.5 – 23.5)−0.51 (−3.06 – 1.69)0.55 (0 – 1.98)Cook Celect (n=105)0.43 (−19.8–21.0)−0.07 (−4.45–3.31)0.48 (0–1.92)Cook Tulip (n=3)0.77 (−1.5 – 2.9)−0.45 (−1.54 – .36)0.24 (0 – 0.37)Cordis Optease (n=8)1.19 (−7.7 – 13.2)0.72 (−3.6 – 10.0)0.17 (0 – 0.54) Open table in a new tab Four families of IVC filters were compared for various stability characteristics.