title: Factors associated with outcome after interventional treatment of symptomatic iliac vein compression syndrome.
abstract: BACKGROUND
  Iliac vein compression syndrome (IVCS) results from compression of the left iliac vein by the overlying right iliac artery against the pelvic brim. In many cases, patients are symptomatic. In symptomatic cases, management consists of angioplasty and stenting. Although therapy is often initially successful, factors associated with long-term outcome have been poorly defined. The purpose of this study was to identify factors associated with stent patency.
  
  
  METHODS
  The medical records of all patients who underwent iliac vein percutaneous transluminal angioplasty and stenting from January 1996 to December 2006 for symptomatic IVCS were reviewed retrospectively. There were 50 women and 8 men, with a mean age of 42 years (median, 39 years; range, 17-71 years). Primary, assisted primary, and secondary patency rates were determined. Patient characteristics and clinical variables were evaluated by univariate and multivariate analysis to determine association with vein patency.
  
  
  RESULTS
  Symptoms consisted of lower extremity swelling (81%) and lower extremity pain (67%). Iliac vein obstruction was treated with pharmacologic thrombolysis (31% of patients) and mechanical thrombus fragmentation (17% of patients). The primary, assisted primary, and secondary patency rates of angioplasty/stenting were 74.1%, 79.7%, and 85.8% at 1 year and 38.1%, 62.8%, and 73.8% at 5 years, respectively. Using a Cox proportional risk model, male sex (hazard ratio, 6.5; P = .001), recent trauma (hazard ratio, 5.3; P = .001), and age younger than 40 years (hazard ratio, 3.8; P = .015) were associated with decreased primary patency. In the absence of any risk factors, primary patency was 94.4% at 1 year and 63.0% at 5 years, decreasing to 28.6% and 0% for two or more risk factors.
  
  
  CONCLUSIONS
  Patency rates for iliac vein percutaneous transluminal angioplasty and stenting in patients with IVCS can potentially be predicted on the basis of a multivariate model. Assessing risk factors allows for patient stratification and appropriate clinical decision making. Prospective validation of these variables is necessary.
authors: Department of Surgery, Section of Vascular Surgery, University of Michigan, Ann Arbor, MI 48109, USA. bknipp@med.umich.edu
authors: Brian S
authors: BS
authors: Knipp
authors: Eric
authors: E
authors: Ferguson
authors: David M
authors: DM
authors: Williams
authors: Narasimham J
authors: NJ
authors: Dasika
authors: Wojciech
authors: W
authors: Cwikiel
authors: Peter K
authors: PK
authors: Henke
authors: Thomas W
authors: TW
authors: Wakefield
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000800:Angioplasty, Balloon; D003251:Constriction, Pathologic / Q000175:diagnosis / Q000628:therapy; D005260:Female; D006801:Humans; D007084:Iliac Vein; D008297:Male; D008875:Middle Aged; D016491:Peripheral Vascular Diseases / Q000150:complications / Q000175:diagnosis / Q000628:therapy*; D015607:Stents; D016019:Survival Analysis