title: Mid- to long-term outcome comparison of the Medtronic Hancock II and bi-leaflet mechanical aortic valve replacement in patients younger than 60 years of age: a propensity-matched analysis.
abstract: OBJECTIVE
  This study aims to compare mid-long-term clinical outcomes between patients younger than 60 years of age undergoing bioprosthetic and mechanical aortic valve replacement.
  
  
  METHODS
  From January 2002 to December 2009, patients younger than 60 years of age who received Medtronic Hancock II porcine bioprostheses were selected and compared with those who received mechanical bi-leaflet valves in the aortic position. A stepwise logistic regression propensity score identified a subset of 112 evenly matched patient-pairs. Mid-long-term outcomes of survival, valve-related reoperations, thromboembolic events and bleeding events were assessed.
  
  
  RESULTS
  The follow-up was only 95.1% complete. Fourteen measurable variables were statistically similar for the matched cohort. Postoperative in-hospital mortality was 3.6% (bioprosthetic valves) and 2.7% (mechanical valves) (P = 0.700). Survival at 5 and 10 years was 96.3 and 88.7% for patients receiving bioprosthetic valve replacement versus 96.3 and 87.9% for patients receiving mechanical valve replacement (P = 0.860), respectively. At 5 and 10 years after operations, freedom from valve-related reoperation was 97.2 and 94.8% for patients receiving mechanical valve replacement, and 96.3 and 90.2% for patients receiving bioprosthetic valve replacement (P = 0.296), respectively. There was no difference between freedom from thromboembolic events (P = 0.528) and bleeding events (P = 0.128) between the matched groups during the postoperative 10 years.
  
  
  CONCLUSIONS
  In patients younger than 60 years of age undergoing aortic valve replacement, mid-long-term survival rate was similar for patients receiving bioprosthetic versus mechanical valve replacement. Bioprosthetic valves were associated with a trend for a lower risk of anticoagulation treatment and did not have significantly greater likelihood of a reoperation. These findings suggest that a bioprosthetic valve may be a reasonable choice for AVR in patients younger than 60 years of age.
authors.affiliation: Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Yin
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Si
authors.initials: S
authors.lastname: Chen
authors.affiliation: Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Jiawei
authors.initials: J
authors.lastname: Shi
authors.affiliation: Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Geng
authors.initials: G
authors.lastname: Li
authors.affiliation: Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China dongnianguo@hotmail.com.
authors.forename: Nianguo
authors.initials: N
authors.lastname: Dong
mesh_terms: D000328:Adult; D000367:Age Factors; D000925:Anticoagulants / Q000009:adverse effects; D001021:Aortic Valve / Q000503:physiopathology / Q000601:surgery*; D001705:Bioprosthesis; D016009:Chi-Square Distribution; D018572:Disease-Free Survival; D005260:Female; D006349:Heart Valve Diseases / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology / Q000601:surgery*; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation* / Q000401:mortality; D006470:Hemorrhage / Q000139:chemically induced; D017052:Hospital Mortality; D006801:Humans; D053208:Kaplan-Meier Estimate; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D057216:Propensity Score; D011474:Prosthesis Design; D012189:Retrospective Studies; D012307:Risk Factors; D013923:Thromboembolism / Q000209:etiology / Q000517:prevention & control; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000925:Anticoagulants
keywords: Aortic valve replacement; Clinical trials; Heart valve prosthesis; Outcome; Younger patients