title: Dysfunction of mechanical heart valve prosthesis: experience with surgical management in 48 patients.
abstract: BACKGROUND
  Dysfunction of mechanical heart valve prostheses is an unusual but potentially lethal complication after mechanical prosthetic valve replacement. We seek to report our experience with mechanical valve dysfunction regarding etiology, surgical techniques and early outcomes.
  
  
  METHODS
  Clinical data of 48 patients with mechanical valve dysfunction surgically treated between October 1996 and June 2011 were analyzed.
  
  
  RESULTS
  Mean age was 43.7±10.9 years and 34 were female (70.8%). The median interval from primary valve implantation to dysfunction was 44.5 months (range, 1 hour to 20 years). There were 21 emergent and 27 elective reoperations. The etiology was thrombosis in 19 cases (39.6%), pannus in 12 (25%), thrombosis and pannus in 11 (22.9%), improper disc orientation in 2 (4.1%), missing leaflet in 1 (2.1%), excessively long knot end in 1 (2.1%), endogenous factor in 1 (2.1%) and unidentified in 1 (2.1%). Surgical procedure was mechanical valve replacement in 37 cases (77.1%), bioprosthetic valve replacement in 7 (14.9%), disc rotation in 2 (4.2%) and excision of excessive knot end in 1 (2.1%). Early deaths occurred in 7 patients (14.6%), due to low cardiac output in 3 (6.3%), multi-organ failure in 2 (4.2%) and refractory ventricular fibrillation in 2 (4.2%). Complications occurred in 10 patients (20.8%).
  
  
  CONCLUSIONS
  Surgical management of mechanical valve dysfunction is associated with significant mortality and morbidity. Earlier identification and prompt reoperation are vital to achieving better clinical outcomes. The high incidence of thrombosis in this series highlights the need for adequate anticoagulation and regular follow-up after mechanical valve replacement.
authors.affiliation: 1 Department of Cardiovascular Surgery, Fu Wai Hospital and Cardiovascular Institute, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, China ; 2 Department of Cardiothoracic Surgery, First Hospital of Kashgar Prefecture, Shinjang 844000, China.
authors.forename: Wei-Guo
authors.initials: WG
authors.lastname: Ma
authors.affiliation: 1 Department of Cardiovascular Surgery, Fu Wai Hospital and Cardiovascular Institute, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, China ; 2 Department of Cardiothoracic Surgery, First Hospital of Kashgar Prefecture, Shinjang 844000, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Hou
authors.affiliation: 1 Department of Cardiovascular Surgery, Fu Wai Hospital and Cardiovascular Institute, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, China ; 2 Department of Cardiothoracic Surgery, First Hospital of Kashgar Prefecture, Shinjang 844000, China.
authors.forename: Adiljan
authors.initials: A
authors.lastname: Abdurusul
authors.affiliation: 1 Department of Cardiovascular Surgery, Fu Wai Hospital and Cardiovascular Institute, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, China ; 2 Department of Cardiothoracic Surgery, First Hospital of Kashgar Prefecture, Shinjang 844000, China.
authors.forename: Ding-Xu
authors.initials: DX
authors.lastname: Gong
authors.affiliation: 1 Department of Cardiovascular Surgery, Fu Wai Hospital and Cardiovascular Institute, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, China ; 2 Department of Cardiothoracic Surgery, First Hospital of Kashgar Prefecture, Shinjang 844000, China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Tang
authors.affiliation: 1 Department of Cardiovascular Surgery, Fu Wai Hospital and Cardiovascular Institute, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, China ; 2 Department of Cardiothoracic Surgery, First Hospital of Kashgar Prefecture, Shinjang 844000, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Chang
authors.affiliation: 1 Department of Cardiovascular Surgery, Fu Wai Hospital and Cardiovascular Institute, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, China ; 2 Department of Cardiothoracic Surgery, First Hospital of Kashgar Prefecture, Shinjang 844000, China.
authors.forename: Jian-Ping
authors.initials: JP
authors.lastname: Xu
authors.affiliation: 1 Department of Cardiovascular Surgery, Fu Wai Hospital and Cardiovascular Institute, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100037, China ; 2 Department of Cardiothoracic Surgery, First Hospital of Kashgar Prefecture, Shinjang 844000, China.
authors.forename: Han-Song
authors.initials: HS
authors.lastname: Sun
keywords: Mechanical heart valve prosthesis; dysfunction; outcome; reoperation; surgery