title: Independent factors associated with longevity of prosthetic pulmonary valves and valved conduits.
abstract: OBJECTIVE
  To evaluate the age dependence of variables predictive of pulmonary valve prosthesis replacement, we conducted the following analysis.
  
  
  METHODS
  Retrospective analysis of 945 operations in 726 patients undergoing placement of pulmonary valve prostheses was performed. Age was identified as a strong independent predictor of valve failure. The database was stratified into age-based subsets and predictors of valve replacement were identified within each subset.
  
  
  RESULTS
  For the entire cohort, freedom from valve replacement at 5 years was 81%. Younger age was strongly associated with decreased time to valve replacement by multivariable analysis (hazard ratio: 0.71/log-year, P <.001). Other independent factors included diagnosis, type of prosthesis, and time-dependent requirement for pulmonary valve stent placement. Important predictors of valve failure varied among age groups and are as follows: for Age Less Than 3 Months: valve type; for Age 3 Months To Less Than 2 Years: smaller normalized valve prosthesis size; for Age 2 Years To Less Than 13 Years: sex, smaller normalized valve prosthesis size, placement of endovascular stents, and valve type; for Age 13 Years To 65 Years: smaller normalized valve prosthesis size, placement of endovascular stents, and increased number of previous valve placements.
  
  
  CONCLUSIONS
  Age is a dominant risk factor predictive of pulmonary valve prosthesis failure. A significant interaction exists between age and the effects of diagnosis, valve type, and size on prosthetic pulmonary valve longevity.
authors.affiliation: Divisions of Cardiovascular Surgery and Cardiology, The Hospital for Sick Children, and the University of Toronto Faculty of Medicine, Toronto, Ontario, Canada. chris-calderone@uiowa.edu
authors.forename: C A
authors.initials: CA
authors.lastname: Caldarone
authors.forename: B W
authors.initials: BW
authors.lastname: McCrindle
authors.forename: G S
authors.initials: GS
authors.lastname: Van Arsdell
authors.forename: J G
authors.initials: JG
authors.lastname: Coles
authors.forename: G
authors.initials: G
authors.lastname: Webb
authors.forename: R M
authors.initials: RM
authors.lastname: Freedom
authors.forename: W G
authors.initials: WG
authors.lastname: Williams
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D002648:Child; D002675:Child, Preschool; D019544:Equipment Failure Analysis; D005260:Female; D006350:Heart Valve Prosthesis / Q000009:adverse effects* / Q000145:classification / Q000600:supply & distribution; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects* / Q000295:instrumentation / Q000401:mortality*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D011475:Prosthesis Failure; D011664:Pulmonary Valve / Q000002:abnormalities / Q000601:surgery*; D012189:Retrospective Studies; D012307:Risk Factors; D016019:Survival Analysis; D013997:Time Factors