title: Mitroflow aortic bioprosthesis 5-year follow-up: north american prospective multicenter study.
abstract: BACKGROUND
  The Mitroflow valve (Sorin Group, Milan, Italy) has been in use since 1982 and has shown long-term durability in large studies from European centers but has not been studied for long-term hemodynamics in large standardized multicenter trials. This study sought to assess the hemodynamics of the Mitroflow valve by extending the duration of follow-up in an ongoing prospective multicenter trial conducted in North America.
  
  
  METHODS
  Six sites participated in this midterm study requiring annual follow-up and echocardiographic evaluation using a standardized transthoracic echocardiography acquisition protocol.
  
  
  RESULTS
  There were 276 patients enrolled (age 74±8 years) and 54% were in New York Heart Association (NYHA) functional class III-IV. Follow-up from the time of valve implantation had a mean of 4.0±1.7 years with a cumulative follow-up of 1,102 patient-years. At 5 years of follow-up, 99% of patients were free of moderate or severe aortic regurgitation and 94% were in NYHA functional class I or II. Between baseline and 5 years, mean gradients increased an average of 0.4 to 4.3 mm Hg. The change in effective orifice area was appreciably small (-0.1 to -0.3 cm2) after 5 years. There were 57 deaths (4 early and 53 late) and 9 valve explants.
  
  
  CONCLUSIONS
  The Mitroflow valve implanted in the aortic position has shown to be hemodynamically stable over a 5-year follow-up in an elderly population with a high prevalence of comorbid conditions.
authors: Medstar Health Research Institute at Medstar Washington Hospital Center, Georgetown University School of Medicine, Washington, DC 20010, USA. federico.asch@medstar.net
authors: Federico M
authors: FM
authors: Asch
authors: David
authors: D
authors: Heimansohn
authors: Daniel
authors: D
authors: Doyle
authors: Walter
authors: W
authors: Dembitsky
authors: Francis D
authors: FD
authors: Ferdinand
authors: Jeffrey
authors: J
authors: Swanson
authors: Joseph A
authors: JA
authors: Dearani
authors: Neil J
authors: NJ
authors: Weissman
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001021:Aortic Valve / Q000000981:diagnostic imaging / Q000601:surgery*; D001705:Bioprosthesis; D004452:Echocardiography; D005260:Female; D005500:Follow-Up Studies; D006350:Heart Valve Prosthesis; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D008944:Mitral Valve Insufficiency / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D009656:North America; D011446:Prospective Studies; D011474:Prosthesis Design; D013997:Time Factors; D016896:Treatment Outcome