title: Factors affecting Cook Gunther Tulip and Cook Celect inferior vena cava filter retrieval success.
abstract: OBJECTIVE
  Success rates vary for the retrieval of inferior vena cava filters (IVCFs). The optimal retrieval time and factors influencing retrieval success remain unproven. This study aims to determine optimal time and evaluate factors related to successful IVCF retrieval.
  
  
  METHODS
  An institutional prospectively maintained database was reviewed for all IVCF retrieval attempts from 2006 to 2012. Patient demographics, comorbidities, indications for procedure, placement technique, IVCF type, presence of angulation, and time to retrieval were evaluated with respect to success or failure of retrieval. Statistical analyses (t-test, χ(2), correlations, and Kaplan-Meier plots) were performed comparing successful and unsuccessful retrievals.
  
  
  RESULTS
  Of 121 attempted IVCF retrievals, 92 (76%) were successful and 29 (24%) were unsuccessful. There were no significant differences between the successful and unsuccessful attempts in terms of patient demographics, comorbidities, indications for procedure, placement technique, or IVCF type, which included 93 Celect (77%) and 28 Gunther Tulip (23%). Time since IVCF placement was significantly different (P = .025) between the successful and unsuccessful retrieval groups (medians were 105 [7-368] and 162 [43-379] days, respectively). Time since IVCF placement greater than 117 days correlated significantly with unsuccessful IVCF retrieval (R = 0.218; P = .017; odds ratio, 2.88; P = .02). Angulation greater than 20 degrees on anteroposterior radiograph was noted in seven of 29 (24%) unsuccessful retrievals compared with seven of 92 (8%) successful retrievals and was significant (P = .012).
  
  
  CONCLUSIONS
  Cook Gunther Tulip and Celect IVCF retrieval is most likely to be successful within 3 to 4 months of placement. Unsuccessful retrieval attempts are more likely to occur when IVCF position is angulated.
authors.affiliation: Section of Vascular Surgery and Endovascular Therapy, University of Alabama at Birmingham, Birmingham, Ala.
authors.forename: Roan J
authors.initials: RJ
authors.lastname: Glocker
authors.affiliation: Section of Vascular Surgery and Endovascular Therapy, University of Alabama at Birmingham, Birmingham, Ala.
authors.forename: Zdenek
authors.initials: Z
authors.lastname: Novak
authors.affiliation: Section of Vascular Surgery and Endovascular Therapy, University of Alabama at Birmingham, Birmingham, Ala.
authors.forename: Thomas C
authors.initials: TC
authors.lastname: Matthews
authors.affiliation: Section of Vascular Surgery and Endovascular Therapy, University of Alabama at Birmingham, Birmingham, Ala.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Patterson
authors.affiliation: Section of Vascular Surgery and Endovascular Therapy, University of Alabama at Birmingham, Birmingham, Ala.
authors.forename: William D
authors.initials: WD
authors.lastname: Jordan
authors.affiliation: Section of Vascular Surgery and Endovascular Therapy, University of Alabama at Birmingham, Birmingham, Ala.
authors.forename: Benjamin J
authors.initials: BJ
authors.lastname: Pearce
authors.affiliation: Section of Vascular Surgery and Endovascular Therapy, University of Alabama at Birmingham, Birmingham, Ala. Electronic address: mpassman@uabmc.edu.
authors.forename: Marc A
authors.initials: MA
authors.lastname: Passman