title: Outcomes 15 years after valve replacement with a mechanical versus a bioprosthetic valve: final report of the Veterans Affairs randomized trial.
abstract: OBJECTIVE
  The goal of this study was to compare long-term survival and valve-related complications between bioprosthetic and mechanical heart valves.
  
  
  BACKGROUND
  Different heart valves may have different patient outcomes.
  
  
  METHODS
  Five hundred seventy-five patients undergoing single aortic valve replacement (AVR) or mitral valve replacement (MVR) at 13 VA medical centers were randomized to receive a bioprosthetic or mechanical valve.
  
  
  RESULTS
  By survival analysis at 15 years, all-cause mortality after AVR was lower with the mechanical valve versus bioprosthesis (66% vs. 79%, p = 0.02) but not after MVR. Primary valve failure occurred mainly in patients <65 years of age (bioprosthesis vs. mechanical, 26% vs. 0%, p < 0.001 for AVR and 44% vs. 4%, p = 0.0001 for MVR), and in patients > or =65 years after AVR, primary valve failure in bioprosthesis versus mechanical valve was 9 +/- 6% versus 0%, p = 0.16. Reoperation was significantly higher for bioprosthetic AVR (p = 0.004). Bleeding occurred more frequently in patients with mechanical valve. There were no statistically significant differences for other complications, including thromboembolism and all valve-related complications between the two randomized groups.
  
  
  CONCLUSIONS
  At 15 years, patients undergoing AVR had a better survival with a mechanical valve than with a bioprosthetic valve, largely because primary valve failure was virtually absent with mechanical valve. Primary valve failure was greater with bioprosthesis, both for AVR and MVR, and occurred at a much higher rate in those aged <65 years; in those aged > or =65 years, primary valve failure after AVR was not significantly different between bioprosthesis and mechanical valve. Reoperation was more common for AVR with bioprosthesis. Thromboembolism rates were similar in the two valve prostheses, but bleeding was more common with a mechanical valve.
authors.affiliation: Denver VA Medical Center and University of Colorado Health Sciences Center, USA.
authors.forename: K
authors.initials: K
authors.lastname: Hammermeister
authors.forename: G K
authors.initials: GK
authors.lastname: Sethi
authors.forename: W G
authors.initials: WG
authors.lastname: Henderson
authors.forename: F L
authors.initials: FL
authors.lastname: Grover
authors.forename: C
authors.initials: C
authors.lastname: Oprian
authors.forename: S H
authors.initials: SH
authors.lastname: Rahimtoola
mesh_terms: D000368:Aged; D001021:Aortic Valve; D001705:Bioprosthesis; D002423:Cause of Death; D005500:Follow-Up Studies; D006349:Heart Valve Diseases / Q000401:mortality / Q000601:surgery; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation; D006801:Humans; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve; D011183:Postoperative Complications; D011795:Surveys and Questionnaires; D015996:Survival Rate; D014481:United States / Q000453:epidemiology; D014493:United States Department of Veterans Affairs / Q000706:statistics & numerical data*