title: Real-time cardiac magnetic resonance cine imaging with sparse sampling and iterative reconstruction for left-ventricular measures: Comparison with gold-standard segmented steady-state free precession.
abstract: Segmented cine imaging with a steady-state free-precession sequence (Cine-SSFP) is currently the gold standard technique for measuring ventricular volumes and mass, but due to multi breath-hold (BH) requirements, it is prone to misalignment of consecutive slices, time consuming and dependent on respiratory capacity. Real-time cine avoids those limitations, but poor spatial and temporal resolution of conventional sequences has prevented its routine application. We sought to examine the accuracy and feasibility of a newly developed real-time sequence with aggressive under-sampling of k-space using sparse sampling and iterative reconstruction (Cine-RT).
  
  
  
  Stacks of short-axis cines were acquired covering both ventricles in a 1.5T system using gold standard Cine-SSFP and Cine-RT. Acquisition parameters for Cine-SSFP were: acquisition matrix of 224×196, temporal resolution of 39ms, retrospective gating, with an average of 8 heartbeats per slice and 1-2 slices/BH. For Cine-RT: acquisition matrix of 224×196, sparse sampling net acceleration factor of 11.3, temporal resolution of 41ms, prospective gating, real-time acquisition of 1 heart-beat/slice and all slices in one BH. LV contours were drawn at end diastole and systole to derive LV volumes and mass.
  
  
  
  Forty-one consecutive patients (15 male; 41±17years) in sinus rhythm were successfully included. All images from Cine-SSFP and Cine-RT were considered to have excellent quality. Cine-RT-derived LV volumes and mass were slightly underestimated but strongly correlated with gold standard Cine-SSFP. Inter- and intra-observer analysis presented similar results between both sequences.
  
  
  
  Cine-RT featuring sparse sampling and iterative reconstruction can achieve spatial and temporal resolution equivalent to Cine-SSFP, providing excellent image quality, with similar precision measurements and highly correlated and only slightly underestimated volume and mass values.
authors.affiliation: Casa de Saúde São José, Rio de Janeiro, Brazil; Federal University of Rio de Janeiro, Rio de Janeiro, Brazil. Electronic address: gabccamargo@gmail.com.
authors.forename: Gabriel C
authors.initials: GC
authors.lastname: Camargo
authors.affiliation: Clínica de Diagnóstico por Imagem, Rio de Janeiro, Brazil. Electronic address: fmerthal@yahoo.com.br.
authors.forename: Fernanda
authors.initials: F
authors.lastname: Erthal
authors.affiliation: Clínica de Diagnóstico por Imagem, Rio de Janeiro, Brazil. Electronic address: leticiasabioni@hotmail.com.
authors.forename: Leticia
authors.initials: L
authors.lastname: Sabioni
authors.affiliation: Clínica de Diagnóstico por Imagem, Rio de Janeiro, Brazil. Electronic address: filipepenna@me.com.
authors.forename: Filipe
authors.initials: F
authors.lastname: Penna
authors.affiliation: Siemens Healthcare Diagnósticos S.A., São Paulo, Brazil. Electronic address: ralph.strecker@siemens.com.
authors.forename: Ralph
authors.initials: R
authors.lastname: Strecker
authors.affiliation: Siemens Healthcare GmbH, Erlangen, Germany. Electronic address: michaela.schmidt@siemens.com.
authors.forename: Michaela
authors.initials: M
authors.lastname: Schmidt
authors.affiliation: Siemens Healthcare GmbH, Erlangen, Germany. Electronic address: michael.zenge@siemens.com.
authors.forename: Michael O
authors.initials: MO
authors.lastname: Zenge
authors.affiliation: Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Clínica de Diagnóstico por Imagem, Rio de Janeiro, Brazil. Electronic address: ronlima@hotmail.com.
authors.forename: Ronaldo de S L
authors.initials: RS
authors.lastname: Lima
authors.affiliation: Casa de Saúde São José, Rio de Janeiro, Brazil; National Institute of Cardiology, Rio de Janeiro, Brazil. Electronic address: ilangottlieb@gmail.com.
authors.forename: Ilan
authors.initials: I
authors.lastname: Gottlieb
mesh_terms: D000328:Adult; D016477:Artifacts; D062485:Breath Holding; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging; D006352:Heart Ventricles / Q000000981:diagnostic imaging*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D019028:Magnetic Resonance Imaging, Cine; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011446:Prospective Studies; D011877:Radionuclide Imaging; D015203:Reproducibility of Results; D012189:Retrospective Studies; D013599:Systole; D016277:Ventricular Function, Left
keywords: Cardiovascular magnetic resonance; Iterative reconstruction; Real-time; Sparse sampling