title: Age, size, and lead factors alone do not predict venous obstruction in children and young adults with transvenous lead systems.
abstract: BACKGROUND
  Venous occlusion is a recognized complication of transvenous pacing, and lead cross-sectional area indexed to body surface area (BSA) has been used to predict venous obstruction in children.
  
  
  OBJECTIVE
  The aim of this study was to identify the risk factors and incidence of angiographic venous obstruction after transvenous lead implantation in both children and young adults.
  
  
  METHODS
  Contrast venography was obtained in 85 of 90 consecutive patients undergoing repeat pacemaker or ICD procedures from 2002 to 2004 at a single cardiac center. Venograms were graded as complete venous obstruction, significant partial obstruction (>70% with collaterals), or patent.
  
  
  RESULTS
  The cohort had a median age of 15.0 years at implant and was divided into two age groups: 3-12 years (n = 35) and 13 years and over (n = 50). After a median interval of 6.5 years, complete obstruction was seen in 11 of 85 patients (13%) and partial obstruction in another 10 patients (12%). No significant differences were seen in the incidence of obstruction between the two age groups although younger patients had a larger lead indexed to BSA ratio (6.82 vs 5.05, P = 0.005). There were no significant differences between obstructed and nonobstructed patients in relation to age, size, growth, or lead factors.
  
  
  CONCLUSIONS
  Transvenous lead systems implanted in young children have a similar incidence of venous occlusion compared to older patients. Furthermore, patient age, body size, and lead characteristics at implant do not clearly predict venous occlusion.
authors.affiliation: From the Department of Cardiology, Children's Hospital Boston, Boston, Massachusetts, USA.
authors.forename: Yaniv
authors.initials: Y
authors.lastname: Bar-Cohen
authors.forename: Charles I
authors.initials: CI
authors.lastname: Berul
authors.forename: Mark E
authors.initials: ME
authors.lastname: Alexander
authors.forename: Elizabeth B
authors.initials: EB
authors.lastname: Fortescue
authors.forename: Edward P
authors.initials: EP
authors.lastname: Walsh
authors.forename: John K
authors.initials: JK
authors.lastname: Triedman
authors.forename: Frank
authors.initials: F
authors.lastname: Cecchin
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D049628:Body Size; D002648:Child; D002675:Child, Preschool; D003331:Coronary Vessels; D017147:Defibrillators, Implantable / Q000009:adverse effects*; D004867:Equipment Design; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010138:Pacemaker, Artificial / Q000009:adverse effects*; D010690:Phlebography; D011379:Prognosis; D012307:Risk Factors; D014652:Vascular Diseases / Q000000981:diagnostic imaging / Q000209:etiology*