title: Midterm and long-term results of percutaneous endovascular treatment of venous outflow obstruction after pediatric liver transplantation.
abstract: OBJECTIVE
  To evaluate retrospectively the midterm and long-term results of percutaneous endovascular treatment of venous outflow obstruction after pediatric liver transplantation.
  
  
  METHODS
  During a 9-year period, 18 children with obstruction of a hepatic vein (HV) or inferior vena cava (IVC) anastomosis underwent percutaneous transluminal angioplasty (PTA) with balloon dilation or stent placement in case of PTA failure after liver transplantation. Patients' body weights ranged from 7.7 kg to 42.6 kg (mean, 18.8 kg +/- 9). Potential predictors of patency were compared between balloon dilation and stent placement groups.
  
  
  RESULTS
  Forty-two procedures were performed (range, 1-11 per patient; mean, 2). Technical and initial clinical success were achieved in all cases. Major complications included one case of pulmonary artery stent embolization and one case of hemothorax. Three children (25%) with HV obstruction were treated with PTA and nine (75%) were treated with stent placement. Three children with IVC obstruction (75%) were treated with PTA and one (25%) was treated with a stent. There were two children with simultaneous obstruction at the HV and IVC; one was treated with PTA and the other with a stent. Cases of isolated HV stenosis have a higher probability of patency with balloon-expandable stent treatment compared with balloon dilation (P < .05). Follow-up time ranged from 7 days to 9 years (mean, 42 months +/- 31), and the primary assisted patency rate was 100% when stent placement was performed among the first three procedures.
  
  
  CONCLUSIONS
  In cases of venous outflow obstruction resulting from HV and/or IVC lesions after pediatric liver transplantation, percutaneous endovascular treatment with balloon dilation or stent placement is a safe and effective alternative treatment that results in long-term patency.
authors.affiliation: Interventional Radiology Unit, Radiology Institute, Hospital das Clinicas, University of Sao Paulo, Rua Teodoro Sampaio, 352/17, Sao Paulo 05406-000, Brazil. fcarnevale@uol.com.br
authors.forename: Francisco C
authors.initials: FC
authors.lastname: Carnevale
authors.forename: Alexandre T
authors.initials: AT
authors.lastname: Machado
authors.forename: Airton M
authors.initials: AM
authors.lastname: Moreira
authors.forename: Miguel A
authors.initials: MA
authors.lastname: De Gregorio
authors.forename: Lisa
authors.initials: L
authors.lastname: Suzuki
authors.forename: Uenis
authors.initials: U
authors.lastname: Tannuri
authors.forename: Nelson
authors.initials: N
authors.lastname: Gibelli
authors.forename: Joao G
authors.initials: JG
authors.lastname: Maksoud
authors.forename: Giovanni G
authors.initials: GG
authors.lastname: Cerri