title: Percutaneous treatment of venous outflow obstruction in pediatric liver transplants.
abstract: OBJECTIVE
  To evaluate the efficacy and safety of percutaneous dilation in the treatment of impaired venous outflow in pediatric patients with liver transplants.
  
  
  METHODS
  Review was undertaken of the records of 35 procedures to dilate impaired venous outflow in 16 consecutive children (aged 11 days to 17.8 years; mean, 7.2 +/- 5.8 y) after liver transplantation over a period of 8 years. Patients presented clinically with signs or symptoms of obstruction of the hepatic venous or inferior vena cava anastomosis and/or abnormal noninvasive imaging findings and were referred primarily to the interventional radiology department for treatment. None were excluded. Technical and clinical success rates were calculated. After venoplasty, patients with incomplete venographic resolution or pressure gradients exceeding 5 mm Hg were treated with stents. Seven died or required repeat transplantation during the study period for reasons unrelated to venous outflow obstruction. Patency rates were calculated for all other patients with sufficient follow-up in the pediatric hepatology clinic.
  
  
  RESULTS
  The combined technical success rate for venoplasty (12 of 16) and stent placement (three of 16) was 94% (15 of 16), and the clinical success rate was 81% (13 of 16). One minor complication occurred: a transient hypoxic episode. Primary patency rates were 72.7% (eight of 11) at 3 months, 60% (six of 10) at 6 months, 55.6% (five of nine) at 12 months, 50% (four of eight) at 18 months, and 50% (three of six) at 36 months. Primary assisted and secondary patency rates were 90.9% (10 of 11) at 3 months, 90% (nine of 10) at 6 months, 88.9% (eight of nine) at 12 months, 87.5% (seven of eight) at 18 months, and 83.3% (five of six) at 36 months.
  
  
  CONCLUSIONS
  Excellent technical and clinical success rates can be achieved with percutaneous dilation of impaired venous outflow after pediatric liver transplantation. Long-term patency may require repeated interventions.
authors.affiliation: Department of Radiology, The University of Chicago, 5841 South Maryland Avenue, MC2026, Chicago, Illinois 60637, USA. jlorenz@radiology.bsd.uchicago.edu
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: Lorenz
authors.forename: Thuong
authors.initials: T
authors.lastname: Van Ha
authors.forename: Brian
authors.initials: B
authors.lastname: Funaki
authors.forename: Michael
authors.initials: M
authors.lastname: Millis
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Leef
authors.forename: Andrew
authors.initials: A
authors.lastname: Bennett
authors.forename: Jordan
authors.initials: J
authors.lastname: Rosenblum
mesh_terms: D000293:Adolescent; D006502:Budd-Chiari Syndrome / Q000000981:diagnostic imaging / Q000209:etiology* / Q000628:therapy; D002648:Child; D002675:Child, Preschool; D004106:Dilatation / Q000379:methods*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D016031:Liver Transplantation / Q000009:adverse effects*; D011183:Postoperative Complications / Q000000981:diagnostic imaging / Q000209:etiology / Q000628:therapy*; D011859:Radiography; D015642:Radiology, Interventional; D012189:Retrospective Studies; D013927:Thrombosis / Q000209:etiology / Q000628:therapy; D014682:Vena Cava, Inferior