title: A population-based study of inferior vena cava filters in patients with acute venous thromboembolism.
abstract: BACKGROUND
  Our study objective was to describe the frequency, indications, and outcomes after inferior vena cava (IVC) filter placement in a population-based sample of residents of the Worcester, Massachusetts, metropolitan area who had been diagnosed as having acute venous thromboembolism (VTE) in 1999, 2001, and 2003.
  
  
  METHODS
  A retrospective chart review of inpatient and outpatient medical records was conducted. Recorded indication(s) for IVC filter placement was determined among a subset of cases from 3 Worcester tertiary care hospitals. Three thrombosis specialists assessed the appropriateness of IVC filter placement.
  
  
  RESULTS
  Of 1547 greater Worcester residents with validated acute VTE and without a prior IVC filter, 203 (13.1%) had an IVC filter placed after acute VTE. Patients with an IVC filter were older, had more comorbidities, and had a higher mortality rate during 3 years of follow-up. There was unanimous agreement by panel members that the use of an IVC filter was appropriate in 51% of cases and inappropriate in 26% of cases, with no consensus in the remaining 23%.
  
  
  CONCLUSIONS
  In this community-based study, IVC filters were frequently used in the treatment of patients with acute VTE. Placement was deemed to be appropriate in approximately 50% of the patients but was not appropriate or debatable in the remaining cases. Given the increasing use of IVC filters, prospective studies are clearly needed to better define the indications for, and efficacy of, IVC filter placement.
authors.affiliation: Department of Medicine, Divisions of Cardiology and Hematology/Thrombosis, Faculty of Health Sciences, McMaster University, 1200 Main St W, Hamilton, ON L8N 3Z5, Canada. fspence@mcmaster.ca
authors.forename: Frederick A
authors.initials: FA
authors.lastname: Spencer
authors.forename: Shannon M
authors.initials: SM
authors.lastname: Bates
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Goldberg
authors.forename: Darleen
authors.initials: D
authors.lastname: Lessard
authors.forename: Cathy
authors.initials: C
authors.lastname: Emery
authors.forename: Alla
authors.initials: A
authors.lastname: Glushchenko
authors.forename: Joel M
authors.initials: JM
authors.lastname: Gore
authors.forename: Richard H
authors.initials: RH
authors.lastname: White
mesh_terms: D000208:Acute Disease; D000368:Aged; D016009:Chi-Square Distribution; D015897:Comorbidity; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008404:Massachusetts / Q000453:epidemiology; D008875:Middle Aged; D011159:Population Surveillance; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data; D015995:Prevalence; D011655:Pulmonary Embolism / Q000401:mortality / Q000517:prevention & control*; D012189:Retrospective Studies; D012307:Risk Factors; D016306:Vena Cava Filters; D054556:Venous Thromboembolism / Q000150:complications* / Q000401:mortality