title: Free-breathing imaging of the heart using 2D cine-GRICS (generalized reconstruction by inversion of coupled systems) with assessment of ventricular volumes and function.
abstract: OBJECTIVE
  To assess cardiac function by means of a novel free-breathing cardiac magnetic resonance imaging (MRI) strategy.
  
  
  METHODS
  A stack of ungated 2D steady-state free precession (SSFP) slices was acquired during free breathing and reconstructed as cardiac cine imaging based on the generalized reconstruction by inversion of coupled systems (GRICS). A motion-compensated sliding window approach allows reconstructing cine movies with most motion artifacts cancelled. The proposed reconstruction uses prior knowledge from respiratory belts and electrocardiogram recordings and features a piecewise linear model that relates the electrocardiogram signal to cardiac displacements. The free-breathing protocol was validated in six subjects against a standard breath-held protocol.
  
  
  RESULTS
  Image sharpness, as assessed by the image gradient entropy, was comparable to that of breath-held images and significantly better than in uncorrected images. Volumetric parameters of cardiac function in the left ventricle (LV) and right ventricle (RV) were similar, including end-systolic volumes, end-diastolic volumes and mass, stroke volumes, and ejection fractions (with differences of 3% ± 2.4 in the LV and 2.9% ± 4.4 in the RV). The duration of the free-breathing protocol was nearly the same as the breath-held protocol.
  
  
  CONCLUSIONS
  Free-breathing cine-GRICS enables accurate assessment of volumetric parameters of cardiac function with efficient correction of motion.
authors: Imagerie Adaptative Diagnostique et Interventionnelle, Nancy-Université, Nancy, France. pa.vuissoz@chu-nancy.fr
authors: Pierre-André
authors: PA
authors: Vuissoz
authors: Freddy
authors: F
authors: Odille
authors: Brice
authors: B
authors: Fernandez
authors: Maelene
authors: M
authors: Lohezic
authors: Adnane
authors: A
authors: Benhadid
authors: Damien
authors: D
authors: Mandry
authors: Jacques
authors: J
authors: Felblinger
mesh_terms: D000465:Algorithms; D016477:Artifacts; D055424:Cardiac-Gated Imaging Techniques / Q000379:methods*; D005260:Female; D006352:Heart Ventricles; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D016014:Linear Models; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D019047:Phantoms, Imaging; D012119:Respiration; D055815:Young Adult