title: Is High Temporal Resolution Achievable for Paediatric Cardiac Acquisitions during Several Heart Beats? Illustration with Cardiac Phase Contrast Cine-MRI.
abstract: BACKGROUND
  During paediatric cardiac Cine-MRI, data acquired during cycles of different lengths must be combined. Most of the time, Feinstein's model is used to project multiple cardiac cycles of variable lengths into a mean cycle.
  
  
  OBJECTIVE
  To assess the effect of Feinstein projection on temporal resolution of Cine-MRI.
  
  
  METHODS
  1/The temporal errors during Feinstein's projection were computed in 306 cardiac cycles fully characterized by tissue Doppler imaging with 6-phase analysis (from a population of 7 children and young adults). 2/The effects of these temporal errors on tissue velocities were assessed by simulating typical tissue phase mapping acquisitions and reconstructions. 3/Myocardial velocities curves, extracted from high-resolution phase-contrast cine images, were compared for the 6 volunteers with lowest and highest heart rate variability, within a population of 36 young adults.
  
  
  RESULTS
  1/The mean of temporal misalignments was 30 ms over the cardiac cycle but reached 60 ms during early diastole. 2/During phase contrast MRI simulation, early diastole velocity peaks were diminished by 6.1 cm/s leading to virtual disappearance of isovolumic relaxation peaks. 3/The smoothing and erasing of isovolumic relaxation peaks was confirmed on tissue phase mapping velocity curves, between subjects with low and high heart rate variability (p = 0.05).
  
  
  CONCLUSIONS
  Feinstein cardiac model creates temporal misalignments that impair high temporal resolution phase contrast cine imaging when beat-to-beat heart rate is changing.
authors.affiliation: Department of Cardiology, CHU Strasbourg, Strasbourg, France.|Department of Cardiology, CHU Nancy, Nancy, France.|U947, INSERM, Nancy, France.|IADI, University of Lorraine, Nancy, France.
authors.forename: Laurent
authors.initials: L
authors.lastname: Bonnemains
authors.affiliation: U947, INSERM, Nancy, France.|IADI, University of Lorraine, Nancy, France.
authors.forename: Freddy
authors.initials: F
authors.lastname: Odille
authors.affiliation: U947, INSERM, Nancy, France.|IADI, University of Lorraine, Nancy, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Meyer
authors.affiliation: U947, INSERM, Nancy, France.|Clinical Investigation Center (CIC-IT 1433), CHU Nancy, Nancy, France.
authors.forename: Gabriella
authors.initials: G
authors.lastname: Hossu
authors.affiliation: U947, INSERM, Nancy, France.|IADI, University of Lorraine, Nancy, France.|Clinical Investigation Center (CIC-IT 1433), CHU Nancy, Nancy, France.
authors.forename: Jacques
authors.initials: J
authors.lastname: Felblinger
authors.affiliation: U947, INSERM, Nancy, France.|IADI, University of Lorraine, Nancy, France.
authors.forename: Pierre-André
authors.initials: PA
authors.lastname: Vuissoz
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D008858:Microscopy, Phase-Contrast / Q000379:methods*; D009206:Myocardium / Q000378:metabolism*; D055815:Young Adult