title: Factors associated with failed retrieval of the Günther Tulip inferior vena cava filter.
abstract: OBJECTIVE
  To identify potential factors associated with failed retrieval of the Günther Tulip inferior vena cava (IVC) filter.
  
  
  METHODS
  A retrospective review was performed of patients who underwent placement of the Günther 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.
authors: Department of Radiology, University of North Carolina, Chapel Hill, North Carolina 27599-7510, USA.
authors: Joel S
authors: JS
authors: Marquess
authors: Charles T
authors: CT
authors: Burke
authors: Ashley H
authors: AH
authors: Beecham
authors: Robert G
authors: RG
authors: Dixon
authors: Joseph M
authors: JM
authors: Stavas
authors: Alan A
authors: AA
authors: Sag
authors: Gary G
authors: GG
authors: Koch
authors: Matthew A
authors: MA
authors: Mauro
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D020878:Device Removal / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D015994:Incidence; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D017211:Treatment Failure; D016306:Vena Cava Filters / Q000706:statistics & numerical data*; D020246:Venous Thrombosis / Q000453:epidemiology* / Q000601:surgery*