title: Combined saturation/inversion recovery sequences for improved evaluation of scar and diffuse fibrosis in patients with arrhythmia or heart rate variability.
abstract: OBJECTIVE
  To develop arrhythmia-insensitive inversion recovery sequences for improved visualization of myocardial scar and quantification of diffuse fibrosis.
  
  
  METHODS
  A novel preparation pre-pulse, called saturation pulse prepared heart-rate-independent inversion recovery, is introduced, which consists of a combination of saturation and inversion pulses to remove the magnetization history in each heartbeat in late gadolinium enhancement (LGE) imaging and eliminate the need for rest periods in T1 mapping. The proposed LGE and T1 mapping sequences were evaluated against conventional LGE and modified Look-Locker inversion sequences using numerical simulations, phantom and imaging in healthy subjects and patients with suspected or known cardiovascular disease.
  
  
  RESULTS
  Simulations and phantom experiments show that the saturation pulse prepared heart-rate-independent inversion recovery pre-pulse in LGE reduces ghosting artifacts and results in perfect nulling of the healthy myocardium in the presence of arrhythmia. In T1 mapping, saturation pulse prepared heart-rate-independent inversion recovery results in (a) reduced scan time (17 vs. 9 heartbeats), (b) insensitivity to heart rate for long T1, and (c) increased signal homogeneity for short T1. LGE images in a patient in atrial fibrillation during the scan show improved myocardial nulling. In vivo T1 maps demonstrate increased signal homogeneity in blood pools and myocardium.
  
  
  CONCLUSIONS
  The proposed sequences are insensitive to heart rate variability, yield improved LGE images in the presence of arrhythmias, as well as T1 mapping with shorter scan times.
authors: Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA; Computer Assisted Clinical Medicine, University Medical Center Mannheim, Heidelberg University, Mannheim, Germany.
authors: Sebastian
authors: S
authors: Weingärtner
authors: Mehmet
authors: M
authors: Akçakaya
authors: Tamer
authors: T
authors: Basha
authors: Kraig V
authors: KV
authors: Kissinger
authors: Beth
authors: B
authors: Goddu
authors: Sophie
authors: S
authors: Berg
authors: Warren J
authors: WJ
authors: Manning
authors: Reza
authors: R
authors: Nezafat
mesh_terms: D000328:Adult; D000465:Algorithms; D001281:Atrial Fibrillation / Q000150:complications / Q000473:pathology*; D005355:Fibrosis; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D008875:Middle Aged; D017682:Myocardial Stunning / Q000209:etiology / Q000473:pathology*; D009206:Myocardium / Q000473:pathology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity