title: Long-term evaluation of biological versus mechanical prosthesis use at reoperative aortic valve replacement.
abstract: OBJECTIVE
  Recent evidence indicated that the use of a bioprosthesis in young patients at first-time aortic valve replacement (AVR) is associated with an increased reoperation risk, but not with an increase in long-term mortality, when compared with the use of a mechanical valve. However, at reoperative AVR, follow-up data by prosthesis type have been lacking from the literature. Therefore, we examined long-term survival and valve-related complications according to the type of prosthesis used at reoperative AVR.
  
  
  METHODS
  We studied 437 patients who underwent reoperative AVR, at a mean age of 58.6 ± 14.2 years, for failure of a previously implanted aortic valve prosthesis. Thirty-day mortality at reoperative AVR was 6% (n = 27). A bioprosthesis was used in 135 (31%) patients. Patients were subsequently followed up for a mean of 7.6 ± 6.8 years after reoperative AVR.
  
  
  RESULTS
  The use of a bioprosthesis at reoperative AVR was not associated with impaired survival on adjusted analysis (hazard ratio [HR], 0.8 ± 0.4; P = .6). Freedom from thromboembolism, and endocarditis were similar between valve types (both P > .05); however, late postoperative major hemorrhage occurred only in patients who received a mechanical prosthesis at reoperative AVR. Risk factors for third-time AVR included the use of a bioprosthesis (HR, 14.0) and younger age (HR, 1.05 per decreasing year) at reoperative AVR (both P < .001). Thirty-day mortality of third-time AVR was 4% (n = 1/27).
  
  
  CONCLUSIONS
  At reoperative AVR, the use of a bioprosthesis is associated with equivalent long-term survival compared with a mechanical prosthesis. Patients who receive a bioprosthesis at reoperative AVR are less likely to experience major hemorrhage but more likely to require third-time AVR, albeit with an acceptable third-time perioperative mortality risk. Therefore, the patient's informed preferences regarding prosthesis choice should prevail, even in a reoperative context.
authors.affiliation: Division of Cardiac Surgery, University of Ottawa, Ottawa, Ontario, Canada.
authors.forename: Vincent
authors.initials: V
authors.lastname: Chan
authors.forename: B-Khanh
authors.initials: BK
authors.lastname: Lam
authors.forename: Fraser D
authors.initials: FD
authors.lastname: Rubens
authors.forename: Paul
authors.initials: P
authors.lastname: Hendry
authors.forename: Roy
authors.initials: R
authors.lastname: Masters
authors.forename: Thierry G
authors.initials: TG
authors.lastname: Mesana
authors.forename: Marc
authors.initials: M
authors.lastname: Ruel
mesh_terms: D001021:Aortic Valve / Q000601:surgery*; D001705:Bioprosthesis; D005260:Female; D005500:Follow-Up Studies; D006349:Heart Valve Diseases / Q000401:mortality / Q000601:surgery*; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D016016:Proportional Hazards Models; D011446:Prospective Studies; D011475:Prosthesis Failure; D012086:Reoperation; D012307:Risk Factors; D018709:Statistics, Nonparametric; D015996:Survival Rate; D016896:Treatment Outcome