Factors associated with failed retrieval of the Gunther Tulip inferior vena cava filter

PURPOSE: To identify potential factors associated with failed retrieval of the Gunther Tulip inferior vena cava (IVC) filter. MATERIALS AND METHODS: A retrospective review was performed of patients who underwent placement of the Gunther Tulip filter with at least one attempt at filter retrieval over a 3-year period. Patient demographics, filter dwell time, filter angulation, and filter leg protrusion were analyzed. RESULTS: A total of 188 patients were included in the study. Primary retrieval success was achieved in 166 patients (88.3%), for an overall retrieval success rate of 94.2%. The overall mean dwell time was 63 days, whereas the mean dwell time in cases of retrieval failure was 95.4 days. A total of seven filters were in place for longer than 6 months, four of which were successfully retrieved. The degree of filter tilt was not found to be significantly related to retrieval success (P = .36), even though filter angulation was commonly cited as a reason for retrieval failure. On venography, 90.9% of filters that could not be retrieved showed leg protrusion beyond the lumen of the IVC. Finally, increasing patient age also correlated with retrieval failure (P = .01). CONCLUSIONS: Prolonged dwell time and increasing patient age are associated with failed filter retrieval. However, even filters in place for extended periods can be safely removed.