title: Prospective heart tracking for whole-heart magnetic resonance angiography.
abstract: To develop a prospective respiratory-gating technique (Heart-NAV) for use with contrast-enhanced three-dimensional (3D) inversion recovery (IR) whole-heart magnetic resonance angiography (MRA) acquisitions that directly tracks heart motion without creating image inflow artifact.
  
  
  
  With Heart-NAV, one of the startup pulses for the whole-heart steady-state free precession MRA sequence is used to collect the centerline of k-space, and its one-dimensional reconstruction is fed into the standard diaphragm-navigator (NAV) signal analysis process to prospectively gate and track respiratory-induced heart displacement. Ten healthy volunteers underwent non-contrast whole-heart MRA acquisitions using the conventional diaphragm-NAV and Heart-NAV with 5 and 10-mm acceptance windows in a 1.5T scanner. Five patients underwent contrast-enhanced IR whole-heart MRA using a diaphragm-NAV and Heart-NAV with a 5-mm acceptance window.
  
  
  
  For non-contrast whole-heart MRA with both the 5 and 10-mm acceptance windows, Heart-NAV yielded coronary artery vessel sharpness and subjective visual scores that were not significantly different than those using a conventional diaphragm-NAV. Scan time for Heart-NAV was 10% shorter (p < 0.05). In patients undergoing contrast-enhanced IR whole-heart MRA, inflow artifact was seen with the diaphragm-NAV but not with Heart-NAV.
  
  
  
  Compared with a conventional diaphragm-NAV, Heart-NAV achieves similar image quality in a slightly shorter scan time and eliminates inflow artifact. Magn Reson Med 77:759-765, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
authors: Department of Cardiology, Boston Children's Hospital, Boston, Massachusetts, USA.|Department of Pediatrics, Harvard Medical School, Boston, Massachusetts, USA.
authors: Mehdi H
authors: MH
authors: Moghari
authors: Department of Cardiology, Boston Children's Hospital, Boston, Massachusetts, USA.|Department of Pediatrics, Harvard Medical School, Boston, Massachusetts, USA.
authors: Tal
authors: T
authors: Geva
authors: Department of Cardiology, Boston Children's Hospital, Boston, Massachusetts, USA.|Department of Pediatrics, Harvard Medical School, Boston, Massachusetts, USA.
authors: Andrew J
authors: AJ
authors: Powell
mesh_terms: D000465:Algorithms; D057791:Cardiac Imaging Techniques / Q000379:methods*; D006321:Heart / Q000000981:diagnostic imaging*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D019047:Phantoms, Imaging; D015656:Respiratory Mechanics / Q000502:physiology
keywords: prospective motion correction; respiratory motion; self-navigator; whole-heart angiography