title: Suprarenal inferior vena cava filters: a 20-year single-center experience.
abstract: OBJECTIVE
  To assess the clinical safety and efficacy of suprarenal inferior vena cava (IVC) filters during long-term follow-up.
  
  
  METHODS
  In this retrospective study, the authors collected the following data about patients who underwent suprarenal IVC filter placement at their institution between 1988 and 2007: demographics, clinical presentation, indications for filter placement, reasons for placing the filter in the suprarenal IVC, type of filter, frequency of pulmonary embolism (PE) after filter placement, and filter-related problems during follow-up.
  
  
  RESULTS
  Seventy patients (32 male and 38 female patients; mean age, 60 years) had suprarenal IVC filters. Sixty-two patients presented with symptoms of venous thromboembolism (VTE) and eight had incidental asymptomatic VTE at imaging. Indications for filter placement were as follows: contraindication to anticoagulation (n = 48), complications and/or failure of anticoagulation (n = 12), added protection (n = 8), and prophylaxis (n = 2). Suprarenal placement was chosen due to IVC thrombus (n = 41), intrinsic and/or extrinsic narrowing of the infrarenal IVC (n = 9), renal and/or gonadal vein thrombus (n = 3), congenital IVC anomalies (n = 6), pelvic mass (n = 5), pregnancy (n = 3), and other reasons (n = 3). The following filters were used: Greenfield (n = 29), Simon Nitinol (n = 5), Vena-Tech (n = 3), TrapEase (n = 22), OptEase (n = 3), Tulip (n = 6), Bird's Nest (n = 1), and Recovery (n = 1). During follow-up (mean, 573 days +/- 953), postfilter PE was suspected in 10 patients; eight patients underwent computed tomography (CT), one of whom had PE at CT. None developed new symptoms of caval thrombosis. Abdominal CT (performed in 30 patients at a mean of 543 days +/- 768) showed thrombus in the filter in three patients, fracture in one patient, and penetration of the IVC wall in two patients.
  
  
  CONCLUSIONS
  Suprarenal filters are safe and effective in preventing PE. The placement of IVC filters above the renal veins does not carry an added risk of complications.
authors.affiliation: Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 55 Fruit Street, Boston, MA 02114, USA. skalva@partners.org
authors.forename: Sanjeeva P
authors.initials: SP
authors.lastname: Kalva
authors.forename: Chrysanthi
authors.initials: C
authors.lastname: Chlapoutaki
authors.forename: Stephan
authors.initials: S
authors.lastname: Wicky
authors.forename: Alan J
authors.initials: AJ
authors.lastname: Greenfield
authors.forename: Arthur C
authors.initials: AC
authors.lastname: Waltman
authors.forename: Christos A
authors.initials: CA
authors.lastname: Athanasoulis
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010690:Phlebography; D011474:Prosthesis Design; D011475:Prosthesis Failure; D011655:Pulmonary Embolism / Q000000981:diagnostic imaging / Q000209:etiology / Q000517:prevention & control*; D012189:Retrospective Studies; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D016306:Vena Cava Filters / Q000009:adverse effects; D014682:Vena Cava, Inferior / Q000000981:diagnostic imaging / Q000601:surgery*; D054556:Venous Thromboembolism / Q000150:complications / Q000000981:diagnostic imaging / Q000628:therapy*