title: Evolution of mitral valve replacement in children: a 40-year experience.
abstract: BACKGROUND
  This report reviews our 40-year experience with pediatric mitral valve replacement (MVR) with respect to mortality, valve-related morbidity, and reoperation risk factors.
  
  
  METHODS
  From 1970 to 2010, 97 patients have undergone a total of 136 MVRs. Median age was 8 years (2 weeks to 18 years), 41 patients (42%) were less than 5 years, and 16 were infants (17%). Etiology was congenital in 65 patients (67%), rheumatic in 27 (28%), and endocarditis in 5 (5%). Regurgitation was the predominant lesion in 67 patients (69%), stenosis in 23 (24%), and mixed in 7 (7%) patients. Mechanical valves (ball, n=11; or bileaflet disc, n=66) and xenografts (porcine, n=14; bovine, n=2) were used in 93 initial MVR patients. Since 2002, 5 children have undergone Ross MVR with a pulmonary autograft in 3 and an aortic homograft in 2.
  
  
  RESULTS
  Hospital mortality was 6% (6 of 97). There were 23 late deaths and 5 patients have required cardiac transplantation. Thirty-five year actuarial survival was 71%. Age less than 2 years, MVR prior to 1980, atrioventricular septal defect, univentricular heart, and additional left side obstructions were significant predictors of death. Mean follow-up was 12.8±10.1 years (range, 2 months to 38 years). Seventeen patients with mechanical valves experienced systemic emboli in 9 (10%), valve thrombosis in 5 (6%), and bleeding requiring transfusion in 3 (3%) patients. Thirty-two patients required reoperations (35%) from 3 months to 14 years (mean, 6.5±4.4 years) after initial MVR. Actuarial freedom from reoperation at 35 years was 63%. Variables associated with mitral re-replacement were younger age, small weight, valve diameter less than 23 mm, MVR prior to 1980, and type of implanted valves (xenograft, single-leaflet disk, ball-caged, or human valves).
  
  
  CONCLUSIONS
  Pediatric MVR can be performed with low initial mortality but should be reserved for medical and reconstruction failure because reoperation, valve-related complications, and late mortality are high. Bileaflet prostheses larger than 23 mm have the lowest reoperation risk. Ross MVR may offer select patients a durable tissue valve without lifelong anticoagulation and its associated complications.
authors.affiliation: Division of Cardiothoracic Surgery, Indiana University School of Medicine, Indianapolis, Indiana 46202-5123, USA. jobrown@iupui.edu
authors.forename: John W
authors.initials: JW
authors.lastname: Brown
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Fiore
authors.forename: Mark
authors.initials: M
authors.lastname: Ruzmetov
authors.forename: Osama
authors.initials: O
authors.lastname: Eltayeb
authors.forename: Mark D
authors.initials: MD
authors.lastname: Rodefeld
authors.forename: Mark W
authors.initials: MW
authors.lastname: Turrentine
mesh_terms: D000293:Adolescent; D001021:Aortic Valve / Q000601:surgery; D001705:Bioprosthesis; D002648:Child; D002675:Child, Preschool; D004696:Endocarditis / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006330:Heart Defects, Congenital / Q000601:surgery; D016027:Heart Transplantation / Q000706:statistics & numerical data; D006350:Heart Valve Prosthesis / Q000145:classification; D019918:Heart Valve Prosthesis Implantation / Q000706:statistics & numerical data*; D017052:Hospital Mortality; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008943:Mitral Valve / Q000002:abnormalities / Q000601:surgery*; D008944:Mitral Valve Insufficiency / Q000601:surgery; D008946:Mitral Valve Stenosis / Q000601:surgery; D011183:Postoperative Complications / Q000453:epidemiology / Q000517:prevention & control; D011664:Pulmonary Valve / Q000601:surgery; D012086:Reoperation / Q000706:statistics & numerical data; D012189:Retrospective Studies; D012214:Rheumatic Heart Disease / Q000601:surgery; D013923:Thromboembolism / Q000453:epidemiology / Q000517:prevention & control; D016042:Transplantation, Heterotopic; D016896:Treatment Outcome