title: Transapical implantation of a self-expandable aortic valve prosthesis utilizing a novel designed positioning element.
abstract: OBJECTIVE
  To evaluate a new transapical system which utilizes a novel designed positioning element and a two-step positioning mechanism for easy and accurate implantation of transcatheter valves.
  
  
  BACKGROUND
  Transcatheter aortic valve implantation is an important treatment option for non-surgical patients with severe aortic stenosis. However, accurate placement of the transcatheter valve remains challenging.
  
  
  METHODS
  Self-expandable aortic valve prosthesis with a flexibly connected, annulus-like positioning element was implanted through a transapical approach in 12 pigs. The positioning element was separated and can be released independent of the valve prosthesis. During valve implantation, firstly, the positioning element was unsheathed and fixed into the aortic sinus. Then, the prosthetic valve was guided to an anatomically oriented position and deployed. Six animals were followed up to 180 days.
  
  
  RESULTS
  With the help of the positioning element, all 12 valves were successfully deployed at the anticipated site. The valve release procedure took an average of 7.3 ± 2.5 min. The mean transvalvular pressure gradient was 2.8 ± 1.1 mm Hg at valve deployment. Of the six chronic animals, the mean transvalvular pressure gradient was 3.0 ± 1.0 mm Hg on day 7, and 2.9 ± 1.6 mm Hg on day 180 (P = 0.91). No migration, embolization, or coronary obstruction was observed during surgery and at necropsy. Pathological examination showed anatomically correct positioning of the prosthetic valve without signs of thrombosis or calcification.
  
  
  CONCLUSIONS
  In this study, we confirmed the feasibility of the J-Valve transapical system for transapical implantation through a two-step process. Satisfactory hemodynamic and pathological performance during a follow-up of 180 days was demonstrated. © 2016 Wiley Periodicals, Inc.
authors.affiliation: Center of Cardiac Surgery for Adults, State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100037, People's Republic of China.|Animal experimental center & Beijing Key Laboratory of Pre-clinical Research and Evaluation for Cardiovascular Implant Materials, State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100037, People's Republic of China.
authors.forename: Xiaopeng
authors.initials: X
authors.lastname: Liu
authors.affiliation: Center of Cardiac Surgery for Adults, State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100037, People's Republic of China.|Animal experimental center & Beijing Key Laboratory of Pre-clinical Research and Evaluation for Cardiovascular Implant Materials, State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100037, People's Republic of China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Tang
authors.affiliation: Animal experimental center & Beijing Key Laboratory of Pre-clinical Research and Evaluation for Cardiovascular Implant Materials, State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100037, People's Republic of China.
authors.forename: Fuliang
authors.initials: F
authors.lastname: Luo
authors.affiliation: Animal experimental center & Beijing Key Laboratory of Pre-clinical Research and Evaluation for Cardiovascular Implant Materials, State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100037, People's Republic of China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Tian
authors.affiliation: Center of Cardiac Surgery for Adults, State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100037, People's Republic of China.
authors.forename: Kai
authors.initials: K
authors.lastname: Li
authors.affiliation: Animal experimental center & Beijing Key Laboratory of Pre-clinical Research and Evaluation for Cardiovascular Implant Materials, State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100037, People's Republic of China.
authors.forename: Jiakang
authors.initials: J
authors.lastname: Sun
authors.affiliation: Animal experimental center & Beijing Key Laboratory of Pre-clinical Research and Evaluation for Cardiovascular Implant Materials, State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100037, People's Republic of China.
authors.forename: Liujun
authors.initials: L
authors.lastname: Jia
authors.affiliation: Center of Cardiac Surgery for Adults, State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100037, People's Republic of China.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
mesh_terms: D000818:Animals; D001021:Aortic Valve / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology; D006328:Cardiac Catheterization / Q000295:instrumentation* / Q000379:methods; D005240:Feasibility Studies; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation* / Q000379:methods; D006439:Hemodynamics; D023421:Models, Animal; D011474:Prosthesis Design; D015641:Radiography, Interventional; D013552:Swine; D013556:Swine, Miniature; D013997:Time Factors
keywords: anatomically correct positioning; preclinical evaluation; transapical aortic valve implantation; two-step positioning mechanism