An analysis of factors associated with increased fluoroscopy time or the need for complex techniques at IVC filter retrieval.

OBJECTIVES

To evaluate factors associated with increased fluoroscopy time or the need for complex techniques at IVC filter retrieval.

METHODS

This is a single-institution retrospective cohort study of 187 consecutive patients who underwent IVC filter retrieval. An analysis was performed on associations of patient factors with increased fluoroscopy time and/or the need for complex retrieval techniques. A complex retrieval was defined as one requiring more than standard sheath and snare technique.

RESULTS

Access vein during filter placement was not associated with filter tilt at placement or removal (p = 0.61 and 0.48). Neither the direction of the hook nor its relationship to the tilt was associated with the need for complex retrieval or increased retrieval fluoroscopy time (p = 0.25, 0.23, p = 0.18, 0.23). Tilt angle at placement correlated with hook apposition at time of removal (p = 0.01). Hook apposition was associated with complex retrieval and increased fluoroscopy time (p < 0.01). Larger tilt angle at placement was not associated with complex retrieval (p = 0.22), but a larger angle at removal was (p < 0.01). Longer dwell time correlated with the need for complex retrieval (p = 0.02). Filter type, sex, and age were not associated with complex retrievals (p = 0.58, p = 0.90, p = 0.99).

CONCLUSION

Contrary to previous hypotheses and studies, access vein for filter placement did not affect filter tilting, and direction of filter hook-tilt relationship did not affect retrieval fluoroscopy time or the need for complex retrieval techniques. Increased filter placement angle was associated with a larger angle at removal and hook-wall apposition, both of which were associated with complex retrievals.

KEY POINTS

• Filter hook orientation did not correlate with retrieval complexity. • Filter insertion vein did not correlate with filter tilt. • Filter tilt and hook apposition to the caval wall at the time of retrieval correlated with retrieval procedure complexity.