title: Real-time magnetic resonance-guided aortic valve replacement using Engager valve.
abstract: OBJECTIVE
  New-generation stented bioprostheses coupled with better imaging modalities are expanding the clinical utility of transcatheter aortic valve replacement (TAVR). This study aimed at evaluating the feasibility of real-time cardiovascular magnetic resonance (rtCMR) -guided TAVR using the Medtronic Engager aortic valve system in a preclinical model.
  
  
  METHODS
  The Engager delivery device was slightly modified to make it CMR-compatible. Ten Yucatan swine underwent rtCMR-guided transapical TAVR. Postplacement phase-contrast and first-pass perfusion CMR sequences were used to evaluate for aortic regurgitation and myocardial perfusion, respectively.
  
  
  RESULTS
  Real-time CMR provided excellent visualization of cardiac anatomy during TAVR. Nine of 10 animals had proper valve placement in the aortic annulus as determined by CMR and confirmed by necropsy inspection. Postplacement phase-contrast scans confirmed no intravalvular or paravalvular leaks. Perfusion scans demonstrated sufficient coronary flow. Roentgenographs confirmed proper placement of the prostheses.
  
  
  CONCLUSIONS
  The Engager valve can be implanted transapically under rtCMR guidance with a modified, CMR-compatible delivery device in a preclinical model. Cardiovascular magnetic resonance allowed for accurate preplacement evaluation, real-time guidance, and postplacement functional assessment.
authors.affiliation: Cardiothoracic Surgery Research Program, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland.
authors.forename: Bogdan A
authors.initials: BA
authors.lastname: Kindzelski
authors.affiliation: Cardiothoracic Surgery Research Program, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland.
authors.forename: Ming
authors.initials: M
authors.lastname: Li
authors.affiliation: Cardiothoracic Surgery Research Program, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland.
authors.forename: Dumitru
authors.initials: D
authors.lastname: Mazilu
authors.affiliation: Cardiothoracic Surgery Research Program, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland.
authors.forename: Timothy
authors.initials: T
authors.lastname: Hunt
authors.affiliation: Cardiothoracic Surgery Research Program, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland. Electronic address: horvathka@mail.nih.gov.
authors.forename: Keith A
authors.initials: KA
authors.lastname: Horvath
mesh_terms: D000818:Animals; D001021:Aortic Valve / Q000601:surgery*; D001024:Aortic Valve Stenosis / Q000601:surgery*; D001705:Bioprosthesis; D004195:Disease Models, Animal; D006350:Heart Valve Prosthesis; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D011474:Prosthesis Design; D025321:Surgery, Computer-Assisted / Q000379:methods*; D013552:Swine; D065467:Transcatheter Aortic Valve Replacement / Q000379:methods*