title: Hancock II bioprosthesis for aortic valve replacement: the gold standard of bioprosthetic valves durability?
abstract: BACKGROUND
  This study examined the long-term durability of the Hancock II bioprosthesis (Medtronic, Minneapolis, MN) in the aortic position.
  
  
  METHODS
  From 1982 to 2004, 1134 patients underwent aortic valve replacement (AVR) with Hancock II bioprosthesis and were prospectively monitored. Mean patient age was 67 +/- 11 years; 202 patients were younger than 60, 402 were 60 to 70, and 526 were older than 70. Median follow-up was 12.2 years and 99.2% complete. Valve function was assessed in 94% of patients. Freedom from adverse events was estimated by the Kaplan-Meier method.
  
  
  RESULTS
  Survival at 20 and 25 years was 19.2% +/- 2% and 6.7% +/- 2.8%, respectively, with only 34 and 3 patients at risk. Survival at 20 years was 54.9% +/- 6.4% in patients younger than 60 years, 22.7% +/- 3.3% in those 60 to 70, and 2.4% +/- 1.9% in those older than 70 (p = 0.01). Structural valve deterioration developed in 67 patients aged younger than 60, in 18 patients aged 60 to 70, and in 2 patients older than 70. The freedom from structural valve deterioration at 20 years was 63.4% +/- 4.2% in the entire cohort, 29.2% +/- 5.7% in patients younger than 60 years, 85.2% +/- 3.7% in patients aged 60 to 70, and 99.8% +/- 0.2% in patients older than 70 (truncated at 18 years). Repeat AVR was performed in 104 patients (74 for structural valve failure, 16 for endocarditis, and 14 for other reasons). At 20 years, the overall freedom from AVR was 65.1% +/- 4% for any reason, 29.8% +/- 5.4% in patients younger than 60 years, 86.8% +/- 3.3% in patients 60 to 70, and 98.3% +/- 0.6% in patients older than 70.
  
  
  CONCLUSIONS
  Hancock II bioprosthesis is a very durable valve in patients 60 years and older and is probably the gold standard of bioprosthetic valve durability in this patient population.
authors: Division of Cardiovascular Surgery of Peter Munk Cardiac Centre, Toronto General Hospital and University of Toronto, Toronto, Ontario, Canada. tirone.david@uhn.on.ca
authors: Tirone E
authors: TE
authors: David
authors: Susan
authors: S
authors: Armstrong
authors: Manjula
authors: M
authors: Maganti
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001021:Aortic Valve / Q000601:surgery*; D001705:Bioprosthesis / Q000009:adverse effects; D005260:Female; D006350:Heart Valve Prosthesis / Q000009:adverse effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology / Q000209:etiology; D011446:Prospective Studies; D011474:Prosthesis Design; D013997:Time Factors; D055815:Young Adult