title: Mitral valve replacement in children: mortality, morbidity, and haemodynamic status up to medium term follow up.
abstract: OBJECTIVE
  To investigate the outcome of mechanical mitral valve replacement in children after up to 11 years of follow up.
  
  
  METHODS
  Retrospective analysis of case records. Operative survivors underwent echocardiographic studies to define current haemodynamic status and prosthetic valve function.
  
  
  METHODS
  Tertiary referral centre.
  
  
  METHODS
  All 54 children who underwent mitral valve replacement between January 1987 and December 1997.
  
  
  RESULTS
  30 day mortality was 20.3% and was associated with small valve size and supra-annular position. The actuarial freedom from the following events at five years (70% confidence interval (CI)) was: death, including 30 day mortality and transplantation, 68% (70% CI 62% to 75%); bleeding, 89% (70% CI 84% to 94%); non-structural valve dysfunction and reoperation, 92% (70% CI 87% to 97%). The incidence of endocarditis and thromboembolism was low and there was no structural valve failure. Event-free survival was 52% (70% CI 45% to 60%). Low weight, young age, and small valve size increased the chance of death or reoperation. On echocardiography, left ventricular dilatation and wall motion abnormalities were often observed. A high mean gradient over the prosthesis was associated with small valve size but not with length of follow up.
  
  
  CONCLUSIONS
  With the use of mechanical prostheses for mitral valve replacement in children, the problem of structural valve failure is no longer an issue. However, the procedure is still associated with a high complication rate, both at surgery and during follow up, and should therefore be reserved for patients in whom valve repair is not technically feasible.
authors.affiliation: Cardiothoracic Unit, Great Ormond Street Hospital for Children NHS Trust, London WC1N 3JH, UK.
authors.forename: C
authors.initials: C
authors.lastname: van Doorn
authors.forename: R
authors.initials: R
authors.lastname: Yates
authors.forename: V
authors.initials: V
authors.lastname: Tsang
authors.forename: M
authors.initials: M
authors.lastname: deLeval
authors.forename: M
authors.initials: M
authors.lastname: Elliott
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D005500:Follow-Up Studies; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects* / Q000379:methods / Q000401:mortality; D006439:Hemodynamics; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008943:Mitral Valve / Q000601:surgery*; D011183:Postoperative Complications / Q000401:mortality; D012189:Retrospective Studies; D012307:Risk Factors; D015996:Survival Rate; D016896:Treatment Outcome