Mechanisms of Günther Tulip filter tilting during transfemoral placement

Diagn Interv Imaging. 2017 Jul-Aug;98(7-8):543-549. doi: 10.1016/j.diii.2017.01.009. Epub 2017 Feb 15.

Abstract

Objective: The purpose of this study was to characterize the mechanisms of Günther Tulip filter (GTF) tilting during transfemoral placement in an experimental model with further validation in a clinical series.

Materials and methods: In an experimental study, 120 GTF placements in an inferior vena cava (IVC) model were performed using 6 configurations of pre-deployment filter position. The angle between the pre-deployment filter axis and IVC axis, and the proximity of the constrained filter legs to IVC wall prior to deployment were evaluated. The association of those pre-deployment factors with post-deployment filter tilting was analyzed. The association noted in the experimental study was then evaluated in a retrospective clinical series of 21 patients.

Results: In the experimental study, there was a significant association between the pre-deployment angle and post-deployment filter tilting (P<0.0001). With a low pre-deployment angle (≤5°), a significant association was noted between filter tilting and the proximity of the constrained filter legs to the far IVC wall (P=0.001). In a retrospective clinical study, a significant association between the pre-deployment angle and post-deployment filter tilting was also noted with a linear regression model (P=0.026).

Conclusion: Significant association of the pre-deployment angle with post-deployment GTF tilting was shown in both the experimental and clinical studies. The experimental study also showed that proximity of filter legs is relevant when pre-deployment angle is small. Addressing these factors may result in a lower incidence of filter tilting.

Keywords: Experimental studies; Inferior vena cava; Inferior vena cava filter; Interventional imaging.