title: Kinetic index combining native and postcontrast myocardial T1 in hypertrophic cardiomyopathy.
abstract: BACKGROUND
  To evaluate ability of pre- and postcontrast apparent T1* indices, as well as their combination to characterize myocardial structural changes in hypertrophic cardiomyopathy (HCM).
  
  
  METHODS
  Study protocol was approved by institutional review board and informed consent was obtained. T1 mapping was performed using MOLLI sequence (1.5T magnet) on: (i) tubes with known T1 and varied heart-rates (HR), (ii) 17 HCM (55 ± 15 years) and 18 controls (49 ± 16 years), before contrast and every 5 min over 20 min postcontrast. Global and segmental native T1 (T1*Native ), extracellular volume (ECV) and percentage of decrease in myocardial T1* (T1*decay = 100·[1-T1*Post-contrast /T1*Native ]) were estimated. Correlation coefficients of associations between T1 and LV indices, such as left ventricular wall thickness (WT) and mass index (LVMi) were provided. Receiver operator curve analysis was performed on per-patient basis to assess ability of T1* indices to identify HCM.
  
  
  RESULTS
  While up to a T1* of 1000 ms the effect of HR was minor, it was more pronounced above 1000 ms. T1*Native (754 ± 76 ms versus 1014 ± 130 ms, P < 0.001), ECV20min (23 ± 5% versus 27 ± 4%, P = 0.005), and T1*decay5, 10, 15 or 20min (38 ± 8% versus 54 ± 6%, P < 0.001) showed significant differences between controls and HCM. Correlation coefficients for associations with WT and LVMi were higher for T1*Native and T1decay, independent of acquisition time (with WT/LVMi: r = 0.58/0.44 (P < 0.05) for T1*Native ; r = 0.23 (P < 0.05)/0.23 for ECV20min ; r > 0.51/ > 0.45(P < 0.05) for T1*decay5, 20min ). T1*Native (97.1%) and T1*decay (91.2%) characterized HCM with higher accuracy (P < 0.02) than ECV (69%).
  
  
  CONCLUSIONS
  T1*Native and T1*decay were able to characterize HCM more accurately than ECV, even in the absence of myocardial hypertrophy and late-gadolinium enhancement.
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, INSERM 1146, CNRS 7371, Laboratoire d'Imagerie Biomédicale, F-75013, Paris, France.
authors.forename: Nadjia
authors.initials: N
authors.lastname: Kachenoura
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, INSERM 1146, CNRS 7371, Laboratoire d'Imagerie Biomédicale, F-75013, Paris, France.|Service de Radiologie Cardiovasculaire, Hôpital Européen Georges Pompidou, Paris, France.|Paris-Centre de recherche Cardiovasculaire, HEGP, INSERM, Paris, France.|Université Paris Descartes, Sorbonne Paris Cité Universités, Faculté de médecine, Paris, France.
authors.forename: Laila
authors.initials: L
authors.lastname: Besson-Hajji
authors.affiliation: Radiology department, Cambridge University Hospitals NHS Foundation Trust, UK.
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Graves
authors.affiliation: GE-Healthcare, UK.
authors.forename: Scott
authors.initials: S
authors.lastname: Reid
authors.affiliation: Service de Radiologie Cardiovasculaire, Hôpital Européen Georges Pompidou, Paris, France.|Paris-Centre de recherche Cardiovasculaire, HEGP, INSERM, Paris, France.|Université Paris Descartes, Sorbonne Paris Cité Universités, Faculté de médecine, Paris, France.
authors.forename: Gilles
authors.initials: G
authors.lastname: Soulat
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, INSERM 1146, CNRS 7371, Laboratoire d'Imagerie Biomédicale, F-75013, Paris, France.|Service de Radiologie Cardiovasculaire, Hôpital Européen Georges Pompidou, Paris, France.
authors.forename: Golmehr
authors.initials: G
authors.lastname: Ashrafpoor
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, INSERM 1146, CNRS 7371, Laboratoire d'Imagerie Biomédicale, F-75013, Paris, France.
authors.forename: Alain
authors.initials: A
authors.lastname: De Cesare
authors.affiliation: Paris-Centre de recherche Cardiovasculaire, HEGP, INSERM, Paris, France.|Université Paris Descartes, Sorbonne Paris Cité Universités, Faculté de médecine, Paris, France.|Assistance Publique-Hôpitaux de Paris, Hôpital Européen Georges Pompidou, Department of Cardiology, Paris, France.
authors.forename: Albert
authors.initials: A
authors.lastname: Hagege
authors.affiliation: Department of Cardiovascular Radiology, Institut de Cardiologie, Hôpital Pitié-Salpêtrière, Paris, France.|Imaging Core Lab, ICAN, Paris, France.
authors.forename: Alban
authors.initials: A
authors.lastname: Redheuil
authors.affiliation: Service de Radiologie Cardiovasculaire, Hôpital Européen Georges Pompidou, Paris, France.|Paris-Centre de recherche Cardiovasculaire, HEGP, INSERM, Paris, France.|Université Paris Descartes, Sorbonne Paris Cité Universités, Faculté de médecine, Paris, France.
authors.forename: Elie
authors.initials: E
authors.lastname: Mousseaux
mesh_terms: D002312:Cardiomyopathy, Hypertrophic / Q000150:complications / Q000473:pathology* / Q000503:physiopathology*; D003198:Computer Simulation; D003287:Contrast Media / Q000008:administration & dosage / Q000493:pharmacokinetics; D005260:Female; D006571:Heterocyclic Compounds / Q000008:administration & dosage / Q000493:pharmacokinetics*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D007700:Kinetics; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D008875:Middle Aged; D008955:Models, Cardiovascular; D009942:Organometallic Compounds / Q000008:administration & dosage / Q000493:pharmacokinetics*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013318:Stroke Volume; D018487:Ventricular Dysfunction, Left / Q000209:etiology / Q000473:pathology* / Q000503:physiopathology*
chemical_list: D003287:Contrast Media; D006571:Heterocyclic Compounds; D009942:Organometallic Compounds; C050823:gadolinium 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetate
keywords: MRI; T1 mapping; extracellular volume; hypertrophic cardiomyopathy