title: Native T1 Relaxation Time and Extracellular Volume Fraction as Accurate Markers of Diffuse Myocardial Fibrosis in Heart Valve Disease　- Comparison With Targeted Left Ventricular Myocardial Biopsy.
abstract: BACKGROUND
  The aim of our study was to investigate the relationship between the cardiac magnetic resonance (CMR)-derived native T1 relaxation time and myocardial extracellular volume (ECV) fraction and the extent of diffuse myocardial fibrosis (DMF) on targeted myocardial left ventricular (LV) biopsy.
  
  
  RESULTS
  The study population consisted of 40 patients (age 63±8 years, 65% male) undergoing valve and/or ascending aorta surgery for severe aortic stenosis (77.5%), root dilatation (7.5%) or valve regurgitation (15%). The T1 relaxation time was assessed in the basal interventricular septum pre- and 10-min post-contrast administration using the modified Look-Locker Inversion recovery sequence prior to surgery. LV myocardial biopsy specimen was obtained during surgery from the basal interventricular septal segment matched with the T1 mapping assessment. The percentage of myocardial collagen was quantified using picrosirius red staining. The average percentage of myocardial collagen was 22.0±14.8%. Both native T1 relaxation time with cutoff value ≥1,010 ms (sensitivity=90%, specificity=73%, area under the curve=0.82) and ECV with cutoff value ≥0.32 (sensitivity=80%, specificity=90%, area under the curve=0.85) showed high accuracy to identify severe (>30%) DMF. The native T1 relaxation time showed significant correlation with LV mass (P<0.01).
  
  
  CONCLUSIONS
  Native T1 relaxation time and ECV at 10 min after contrast administration are accurate markers of DMF. (Circ J 2016; 80: 1202-1209).
authors.affiliation: Department of Cardiology, Institute for Clinical and Experimental Medicine.
authors.forename: Radka
authors.initials: R
authors.lastname: Kockova
authors.forename: Petr
authors.initials: P
authors.lastname: Kacer
authors.forename: Jan
authors.initials: J
authors.lastname: Pirk
authors.forename: Jiri
authors.initials: J
authors.lastname: Maly
authors.forename: Lucie
authors.initials: L
authors.lastname: Sukupova
authors.forename: Viktor
authors.initials: V
authors.lastname: Sikula
authors.forename: Martin
authors.initials: M
authors.lastname: Kotrc
authors.forename: Lucia
authors.initials: L
authors.lastname: Barciakova
authors.forename: Eva
authors.initials: E
authors.lastname: Honsova
authors.forename: Marek
authors.initials: M
authors.lastname: Maly
authors.forename: Josef
authors.initials: J
authors.lastname: Kautzner
authors.forename: David
authors.initials: D
authors.lastname: Sedmera
authors.forename: Martin
authors.initials: M
authors.lastname: Penicka
mesh_terms: D000368:Aged; D015415:Biomarkers; D001706:Biopsy; D003094:Collagen / Q000032:analysis; D005260:Female; D005355:Fibrosis / Q000175:diagnosis / Q000000981:diagnostic imaging*; D006352:Heart Ventricles / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000473:pathology
chemical_list: D015415:Biomarkers; D003094:Collagen