title: Mitral valve replacement in patients under 65 years of age: mechanical or biological valves?
abstract: OBJECTIVE
  There is controversy regarding the optimal choice of prosthetic valves in patients less than 65 years of age requiring mitral valve replacement (MVR). Recently, trends for valve replacement are moving towards biological prosthesis also in younger patients, which is justified by the fact that a later valve-in-valve procedure is feasible in the case of degeneration of the tissue valve. This strategy is increasingly recommended in aortic valve surgery but is questionable for MVR. The purpose of this review is to evaluate current guidelines and analyse evidence for biological MVR in patients under 65 years.
  
  
  RESULTS
  There are differences between guidelines of the American Heart Association and those of the European Society of Cardiology concerning the choice of prostheses in patients undergoing MVR. Although the European Society of Cardiology recommends a mechanical mitral valve in patients under 65 years of age, the American Heart Association does not provide detailed advice for these patients. Mitral valve replacement with biological valves in patients under 65 years is associated with higher rates of reoperation due to structural valve deterioration. In addition, several studies showed a decreased survival after biological MVR.
  
  
  CONCLUSIONS
  Evidence for biological MVR in patients less than 65 years without comorbidities or contraindication for oral anticoagulation does not exist. Recommendations for patients less than 65 years of age should not be blurred by current 'en-vogue' methods for promising but not yet proven valve-in-valve strategies.
authors.affiliation: Department of Cardiovascular Surgery, University Hospital, Berne, Switzerland.
authors.forename: David C
authors.initials: DC
authors.lastname: Reineke
authors.forename: Paul Philipp
authors.initials: PP
authors.lastname: Heinisch
authors.forename: Bernhard
authors.initials: B
authors.lastname: Winkler
authors.forename: Lars
authors.initials: L
authors.lastname: Englberger
authors.forename: Thierry P
authors.initials: TP
authors.lastname: Carrel