title: Mid-term results with 1,503 CarboMedics mechanical valve implants.
abstract: OBJECTIVE
  The CarboMedics bileaflet prosthetic heart valve was introduced in 1986, and first implanted by the authors in March 1991. The aim of this study was to analyze the authors' clinical experience with this valve.
  
  
  METHODS
  Between March 1991 and October 1998, 1,503 valves were implanted in 1,350 patients (758 males, 592 female; mean age 62 +/- 13 years). Follow up was 99% complete and totaled 4,342 patient-years (pt-yr).
  
  
  RESULTS
  The hospital mortality rate was 4.3% (59/1,350). Preoperative NYHA class (p = 0.012), emergency surgery (p = 0.03) and cardiopulmonary bypass time (p = 0.01) were significantly associated with increased risk of operative death (multiple logistic regression). Mean (+/- SEM) survival rates at one and five years were 92.0 +/- 0.7% (n = 1,109) and 80.0 +/- 1.3% (n = 335). Freedom from valve-related complications (linearized rate 5.6%/pt-yr) at one and five years was 89.5 +/- 0.8% (n = 1,031) and 76.3 +/- 1.4% (n = 284). Linearized rates for bleeding events were 2.19%/pt-yr, thromboembolic events 2%/pt-yr, operated valvular endocarditis 0.18%/pt-yr, valve thrombosis 0.14%/pt-yr and non-structural dysfunction 1.22%/pt-yr. Freedom from reoperation at one and five years was 98.5 +/- 0.3% (n = 1,107) and 97.3 +/- 0.5% (n = 334).
  
  
  CONCLUSIONS
  Mid-term results demonstrate that the CarboMedics prosthetic heart valve exhibits a low incidence of valve-related complications.
authors.affiliation: Wessex Cardiothoracic Centre, Southampton General Hospital, UK.
authors.forename: M J
authors.initials: MJ
authors.lastname: Dalrymple-Hay
authors.forename: R K
authors.initials: RK
authors.lastname: Pearce
authors.forename: S
authors.initials: S
authors.lastname: Dawkins
authors.forename: C
authors.initials: C
authors.lastname: Alexiou
authors.forename: M P
authors.initials: MP
authors.lastname: Haw
authors.forename: S A
authors.initials: SA
authors.lastname: Livesey
authors.forename: J L
authors.initials: JL
authors.lastname: Monro
mesh_terms: D000368:Aged; D001021:Aortic Valve / Q000601:surgery; D004696:Endocarditis / Q000453:epidemiology; D005260:Female; D005500:Follow-Up Studies; D006350:Heart Valve Prosthesis / Q000009:adverse effects; D019918:Heart Valve Prosthesis Implantation; D017052:Hospital Mortality; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000601:surgery; D009017:Morbidity; D011183:Postoperative Complications / Q000453:epidemiology; D011474:Prosthesis Design; D012086:Reoperation / Q000706:statistics & numerical data; D013923:Thromboembolism / Q000453:epidemiology; D013997:Time Factors