title: Myocardial T1 and extracellular volume fraction measurement in asymptomatic patients with aortic stenosis: reproducibility and comparison with age-matched controls.
abstract: OBJECTIVE
  (i) To establish the test-retest reproducibility of myocardial T1 and extracellular volume (ECV) fraction measurement in asymptomatic patients with moderate-severe aortic stenosis (AS), (ii) to compare reproducibility using motion-corrected (MOCO) parametric T1 maps for analysis vs. full MOLLI series of images, and (iii) to compare T1 and ECV between patients and age-matched controls.
  
  
  RESULTS
  3 T cardiac MRI was performed twice on 10 patients (median interval 7 days) to assess reproducibility. An additional 40 patients and 22 asymptomatic controls underwent a single MRI. Native T1 and ECV were calculated by outlining the myocardium on T1 maps generated inline, and using an offline T1 fit on the MOCO multiple inversion-time raw image series, in the reproducibility cohort (n = 10). Reproducibility was excellent using the inline T1 maps (CoVs for T1: 1.77%; ECV: 6.52%) and good using the full MOLLI series (CoVs for T1: 8.52%; ECV: 12.98%). On comparing AS and controls, who were well matched for age, gender and co-morbidities, there was no significant difference in the native T1 or ECV (T1 = 1103.32 ± 33.07 vs. 1092.27 ± 34.29; ECV = 0.243 ± 0.019 vs. 0.251 ± 0.026 in patients and controls, P > 0.05), which was maintained even after splitting the patients into moderate and severe AS subgroups.
  
  
  CONCLUSIONS
  The test-retest reproducibility of myocardial T1 quantification using MOLLI is excellent in patients with AS and is highest using inline generated T1 maps for analysis. There was no difference in native myocardial T1 or ECV between asymptomatic patients with moderate-severe AS and age-matched controls without valve disease.
authors: Department of Cardiovascular Sciences, University of Leicester and the NIHR Leicester Cardiovascular Biomedical Research Unit, Glenfield Hospital, Groby Road, Leicester LE3 9QP, UK as707@le.ac.uk.
authors: Anvesha
authors: A
authors: Singh
authors: Department of Cardiovascular Sciences, University of Leicester and the NIHR Leicester Cardiovascular Biomedical Research Unit, Glenfield Hospital, Groby Road, Leicester LE3 9QP, UK.
authors: Mark A
authors: MA
authors: Horsfield
authors: University of Leicester, Leicester LE1 7RH, UK.
authors: Soliana
authors: S
authors: Bekele
authors: Department of Cardiovascular Sciences, University of Leicester and the NIHR Leicester Cardiovascular Biomedical Research Unit, Glenfield Hospital, Groby Road, Leicester LE3 9QP, UK.
authors: Jamal N
authors: JN
authors: Khan
authors: Siemens AG, Healthcare Sector, Erlangen, Germany.
authors: Andreas
authors: A
authors: Greiser
authors: Department of Cardiovascular Sciences, University of Leicester and the NIHR Leicester Cardiovascular Biomedical Research Unit, Glenfield Hospital, Groby Road, Leicester LE3 9QP, UK.
authors: Gerry P
authors: GP
authors: McCann
mesh_terms: D000368:Aged; D001024:Aortic Valve Stenosis / Q000175:diagnosis*; D016022:Case-Control Studies; D045604:Extracellular Fluid; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000473:pathology*; D015588:Observer Variation; D011446:Prospective Studies; D012016:Reference Values; D015203:Reproducibility of Results; D012720:Severity of Illness Index
keywords: ECV; T1 mapping; aortic stenosis; cardiac magnetic resonance imaging