title: A non-contrast self-navigated 3-dimensional MR technique for aortic root and vascular access route assessment in the context of transcatheter aortic valve replacement: proof of concept.
abstract: OBJECTIVE
  Due to the high prevalence of renal failure in transcatheter aortic valve replacement (TAVR) candidates, a non-contrast MR technique is desirable for pre-procedural planning. We sought to evaluate the feasibility of a novel, non-contrast, free-breathing, self-navigated three-dimensional (SN3D) MR sequence for imaging the aorta from its root to the iliofemoral run-off in comparison to non-contrast two-dimensional-balanced steady-state free-precession (2D-bSSFP) imaging.
  
  
  METHODS
  SN3D [field of view (FOV), 220-370 mm(3); slice thickness, 1.15 mm; repetition/echo time (TR/TE), 3.1/1.5 ms; and flip angle, 115°] and 2D-bSSFP acquisitions (FOV, 340 mm; slice thickness, 6 mm; TR/TE, 2.3/1.1 ms; flip angle, 77°) were performed in 10 healthy subjects (all male; mean age, 30.3 ± 4.3 yrs) using a 1.5-T MRI system. Aortic root measurements and qualitative image ratings (four-point Likert-scale) were compared.
  
  
  RESULTS
  The mean effective aortic annulus diameter was similar for 2D-bSSFP and SN3D (26.7 ± 0.7 vs. 26.1 ± 0.9 mm, p = 0.23). The mean image quality of 2D-bSSFP (4; IQR 3-4) was rated slightly higher (p = 0.03) than SN3D (3; IQR 2-4). The mean total acquisition time for SN3D imaging was 12.8 ± 2.4 min.
  
  
  CONCLUSIONS
  Our results suggest that a novel SN3D sequence allows rapid, free-breathing assessment of the aortic root and the aortoiliofemoral system without administration of contrast medium.
  
  
  CONCLUSIONS
  • The prevalence of renal failure is high among TAVR candidates. • Non-contrast 3D MR angiography allows for TAVR procedure planning. • The self-navigated sequence provides a significantly reduced scanning time.
authors.affiliation: Heart & Vascular Center, Medical University of South Carolina, Charleston, SC, USA.|Department of Medicine I, University Hospital Giessen and Marburg, Giessen, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Renker
authors.affiliation: Heart & Vascular Center, Medical University of South Carolina, Charleston, SC, USA.
authors.forename: Akos
authors.initials: A
authors.lastname: Varga-Szemes
authors.affiliation: Heart & Vascular Center, Medical University of South Carolina, Charleston, SC, USA. schoepf@musc.edu.|Department of Radiology and Radiological Science, Medical University of South Carolina, 25 Courtenay Drive, Ashley River Tower, Charleston, SC, 29425-2260, USA. schoepf@musc.edu.
authors.forename: U Joseph
authors.initials: UJ
authors.lastname: Schoepf
authors.affiliation: Heart & Vascular Center, Medical University of South Carolina, Charleston, SC, USA.|1st Department of Medicine, Faculty of Medicine Mannheim, University Medical Centre Mannheim (UMM), University of Heidelberg, Mannheim, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Baumann
authors.affiliation: Advanced Clinical Imaging Technology, Siemens Healthcare IM BM PI, Lausanne, Switzerland.|Department of Radiology, University Hospital (CHUV) and University of Lausanne (UNIL), Lausanne, Switzerland.
authors.forename: Davide
authors.initials: D
authors.lastname: Piccini
authors.affiliation: Siemens AG, Healthcare Sector, Erlangen, Germany.
authors.forename: Michael O
authors.initials: MO
authors.lastname: Zenge
authors.affiliation: Cardiovascular MR Center, Duke University Medical Center, Durham, NC, USA.
authors.forename: Wolfgang G
authors.initials: WG
authors.lastname: Rehwald
authors.affiliation: Siemens AG, Healthcare Sector, Erlangen, Germany.
authors.forename: Edgar
authors.initials: E
authors.lastname: Müller
authors.affiliation: Heart & Vascular Center, Medical University of South Carolina, Charleston, SC, USA.
authors.forename: Jeremy D
authors.initials: JD
authors.lastname: Rier
authors.affiliation: Kerckhoff Heart and Thorax Center, Bad Nauheim, Germany.
authors.forename: Helge
authors.initials: H
authors.lastname: Möllmann
authors.affiliation: Department of Medicine I, University Hospital Giessen and Marburg, Giessen, Germany.
authors.forename: Christian W
authors.initials: CW
authors.lastname: Hamm
authors.affiliation: Heart & Vascular Center, Medical University of South Carolina, Charleston, SC, USA.
authors.forename: Daniel H
authors.initials: DH
authors.lastname: Steinberg
authors.affiliation: Heart & Vascular Center, Medical University of South Carolina, Charleston, SC, USA.|Department of Radiological Sciences, Oncology and Pathology, University of Rome "Sapienza"-Polo Pontino, Latina, Italy.
authors.forename: Carlo N
authors.initials: CN
authors.lastname: De Cecco
mesh_terms: D000328:Adult; D001021:Aortic Valve / Q000473:pathology / Q000601:surgery; D001024:Aortic Valve Stenosis / Q000473:pathology* / Q000601:surgery*; D003287:Contrast Media; D005240:Feasibility Studies; D064368:Healthy Volunteers; D006801:Humans; D021621:Imaging, Three-Dimensional; D018810:Magnetic Resonance Angiography / Q000379:methods; D053783:Magnetic Resonance Imaging, Interventional / Q000379:methods; D008297:Male; D011446:Prospective Studies; D065467:Transcatheter Aortic Valve Replacement / Q000379:methods*
chemical_list: D003287:Contrast Media
keywords: Aortic valve stenosis; Contrast media; Magnetic resonance imaging; Renal insufficiency; Transcatheter aortic valve replacement