title: Transapical mitral valved stent implantation: enhanced survival and decreased paravalvular leakages.
abstract: OBJECTIVE
  This study presents the recent results of transapical implantation of a new design of a mitral valved stent with up to three months follow-up.
  
  
  METHODS
  A self-expanding re-designed mitral valved stent was implanted via transapical approach into the beating heart of eight pigs. Echocardiographic- and hemodynamic parameters were assessed before (n=8), at 1h (n=8), at one month (n=6), at two months (n=2), and at three months (n=1) after implantation and a cardiac CT was conducted.
  
  
  RESULTS
  The stent was successfully deployed in all animals. Two animals died within the first month due to incorrect fixation force. Echocardiographic evaluation showed low gradients (3.9 ± 1.4 mm Hg and 1.9 ± 0.8 mm Hg across the valved stent and aortic valve) and a normal mitral annular plane systolic excursion (1.1 ± 0.2 cm) after one month. No paravalvular leakages (PVL) were detected after 1h. The pulmonary artery pressure did not increase after valved stent implantation (p ≥ 0.106). The pulmonary capillary wedge pressure (PCWP) slightly increased to 16 ± 3 mm Hg after one month (p=0.033). The left ventricular end-diastolic pressure was mildly elevated (15.8 ± 8.6 mm Hg) after one month.
  
  
  CONCLUSIONS
  Secure deployment and correct position of the valved stents were reproducibly achieved in the off-pump implantation procedure. No paravalvular leakages after 1h as well as low gradients, few stent fractures and a normal longitudinal function after one month were achieved with this newly developed and well-aligned prototype. However, a number of challenges have been identified during this study and potential for improvement has been identified.
authors.affiliation: Department of Cardiovascular Surgery, Christian-Albrechts-University of Kiel, School of Medicine, Arnold-Heller-Str. 3, D-24105 Kiel, Germany; Institute of Biomechanics, TUHH Hamburg University of Technology, Denickestraße 15, D-21073 Hamburg, Germany.
authors.forename: Saskia
authors.initials: S
authors.lastname: Pokorny
authors.affiliation: Department of Cardiovascular Surgery, Christian-Albrechts-University of Kiel, School of Medicine, Arnold-Heller-Str. 3, D-24105 Kiel, Germany.
authors.forename: Katharina
authors.initials: K
authors.lastname: Huenges
authors.affiliation: Department of Cardiovascular Surgery, Christian-Albrechts-University of Kiel, School of Medicine, Arnold-Heller-Str. 3, D-24105 Kiel, Germany.
authors.forename: Telse
authors.initials: T
authors.lastname: Bähr
authors.affiliation: Department of Pediatric Cardiology, Christian-Albrechts-University of Kiel, School of Medicine, Arnold-Heller-Str. 3, D-24105 Kiel, Germany.
authors.forename: Jan Hinnerk
authors.initials: JH
authors.lastname: Hansen
authors.affiliation: Department of Pediatric Cardiology, Christian-Albrechts-University of Kiel, School of Medicine, Arnold-Heller-Str. 3, D-24105 Kiel, Germany.
authors.forename: Gunther
authors.initials: G
authors.lastname: Fischer
authors.affiliation: Department of Cardiovascular Surgery, Christian-Albrechts-University of Kiel, School of Medicine, Arnold-Heller-Str. 3, D-24105 Kiel, Germany.
authors.forename: Justus
authors.initials: J
authors.lastname: Gross
authors.affiliation: Institute of Biomechanics, TUHH Hamburg University of Technology, Denickestraße 15, D-21073 Hamburg, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Morlock
authors.affiliation: Department of Cardiovascular Surgery, Christian-Albrechts-University of Kiel, School of Medicine, Arnold-Heller-Str. 3, D-24105 Kiel, Germany.
authors.forename: Jochen
authors.initials: J
authors.lastname: Cremer
authors.affiliation: Department of Cardiovascular Surgery, Christian-Albrechts-University of Kiel, School of Medicine, Arnold-Heller-Str. 3, D-24105 Kiel, Germany. Electronic address: georg.lutter@uksh-kiel.de.
authors.forename: Georg
authors.initials: G
authors.lastname: Lutter
mesh_terms: D000818:Animals; D004867:Equipment Design / Q000592:standards / Q000639:trends*; D019918:Heart Valve Prosthesis Implantation / Q000401:mortality* / Q000592:standards / Q000639:trends*; D008943:Mitral Valve / Q000601:surgery*; D015607:Stents / Q000592:standards / Q000639:trends*; D015996:Survival Rate / Q000639:trends; D013552:Swine
keywords: Mitral valve; Off-pump; Stent design; Transapical; Transcatheter; Valved stent