title: Outcomes of mitral valve replacement in children: a competing-risks analysis.
abstract: OBJECTIVE
  We sought to define patient characteristics, outcomes, and associated factors after mitral valve replacement in children.
  
  
  METHODS
  We included 104 children undergoing at least one mitral valve replacement between 1980 and 2003 and reviewed clinical records. Competing-risks methodology was used to determine time-related prevalence and associated risk factors after initial mitral valve replacement for death and repeat replacement.
  
  
  RESULTS
  The underlying mitral valve disease was congenital in 83%, rheumatic in 13%, Marfan syndrome in 3%, and isolated endocarditis in 1%, with 64% having primarily regurgitation, 16% having stenosis, 20% having both, and 32% having undergone previous valvotomy, valvuloplasty, or repair. There were 137 valve replacements, with 26 patients having more than one. Valve prosthesis type was St Jude Medical in 37%, Bjork-Shiley in 25%, Carbomedics in 20%, Ionescu-Shiley in 10%, and other types in 8%. Both early and late complications were common. Median age at the initial replacement was 5.9 years (range, birth to 19 years). Competing-risks analysis predicted 19% to have died at 15 years after initial replacement, with risk factors including noncongenital valve morphology, lower weight, and longer duration of cardiopulmonary bypass. A repeat replacement was predicted for 71%, with risk factors including the presence of multiple left-heart obstructive lesions and Ionescu-Shiley valve prosthesis.
  
  
  CONCLUSIONS
  Mitral valve replacement might be necessary in children with extremely dysplastic valves and severe hemodynamic impairment or after failed repair. However, with the appropriate selection of the prosthetic valve and reduction of cardiopulmonary bypass time, surgeons might decrease mortality and increase prosthesis longevity.
authors.affiliation: Division of Cardiology, Department of Pediatrics, The Hospital for Sick Children, University of Toronto, 555 University Avenue, Toronto, Ontario, Canada M5G 1X8.
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Kojori
authors.forename: Rui
authors.initials: R
authors.lastname: Chen
authors.forename: Christopher A
authors.initials: CA
authors.lastname: Caldarone
authors.forename: Sandra L
authors.initials: SL
authors.lastname: Merklinger
authors.forename: Anthony
authors.initials: A
authors.lastname: Azakie
authors.forename: William G
authors.initials: WG
authors.lastname: Williams
authors.forename: Glen S
authors.initials: GS
authors.lastname: Van Arsdell
authors.forename: John
authors.initials: J
authors.lastname: Coles
authors.forename: Brian W
authors.initials: BW
authors.lastname: McCrindle
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D005260:Female; D006349:Heart Valve Diseases / Q000151:congenital / Q000209:etiology / Q000601:surgery*; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects / Q000401:mortality; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008943:Mitral Valve / Q000601:surgery*; D011183:Postoperative Complications; D012086:Reoperation; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D016019:Survival Analysis; D016896:Treatment Outcome