title: A comparison of clinical outcomes with retrievable and permanent inferior vena cava filters.
abstract: OBJECTIVE
  To compare the clinical effectiveness of retrievable and permanent inferior vena cava (IVC) filters.
  
  
  METHODS
  A retrospective cohort study of consecutive patients who received retrievable or permanent IVC filters from January 2002 through December 2006 was conducted. Patient characteristics and clinical outcomes were compared with nonparametric and parametric statistics.
  
  
  RESULTS
  IVC filters were placed in 702 patients: 427 (60.8%) received a retrievable filter (RF) and 275 (39.2%) received a permanent filter (PF). Overall, the mean duration of follow-up was 11.5 months: 10.4 months for RF recipients and 13.1 months for PF recipients (P = .025). PF recipients were older (60.6 y +/- 17.0 vs 55.4 y +/- 17.2; P < .0001) and more likely to have underlying cancer (45.8% vs 29.3%; P < .0001). Symptomatic pulmonary embolism (PE) occurred in 11 PF recipients and 20 RF recipients who were receiving ongoing filtration (4.0% vs 4.7%; P = .67). Patients with PFs and RFs with ongoing filtration experienced symptomatic deep vein thrombosis (11.3% vs 12.6%; P = .59) and symptomatic IVC thrombosis (1.1% vs 0.5%; P = .39) at a comparable frequency. Sixty-six RF recipients (15.5%) underwent attempted retrieval, which was successful in 46 (69.7%). No RF recipients experienced a new PE after retrieval during a mean follow-up of 12.0 months.
  
  
  CONCLUSIONS
  In this retrospective cohort study, RFs and PFs provided similar protection from PE with comparable complication rates. Clinicians should select an IVC filter based on the projected duration of filtration needed at the time of placement rather than filter type.
authors.affiliation: Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205-4010, USA. sikhkim@jhmi.edu
authors.forename: Hyun S
authors.initials: HS
authors.lastname: Kim
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Young
authors.forename: Anand K
authors.initials: AK
authors.lastname: Narayan
authors.forename: Kelvin
authors.initials: K
authors.lastname: Hong
authors.forename: Robert P
authors.initials: RP
authors.lastname: Liddell
authors.forename: Michael B
authors.initials: MB
authors.lastname: Streiff
mesh_terms: D015331:Cohort Studies; D005260:Female; D005343:Fibrinolytic Agents / Q000627:therapeutic use; D006801:Humans; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000150:complications; D011655:Pulmonary Embolism / Q000209:etiology; D012189:Retrospective Studies; D016896:Treatment Outcome; D016306:Vena Cava Filters; D020246:Venous Thrombosis / Q000628:therapy
chemical_list: D005343:Fibrinolytic Agents