title: Value of in vivo T2 measurement for myocardial fibrosis assessment in diabetic mice at 11.75 T.
abstract: OBJECTIVE
  The aim of the study was to assess the value of in vivo T2 measurements to noninvasively quantify myocardial fibrosis in diabetic mice at 11.75 T. Diabetic cardiomyopathy is characterized by extracellular matrix alteration and microcirculation impairment. These conditions might provide electrical heterogeneity, which is a substrate for arrhythmogenesis. T1 mapping has been proposed to quantify diffuse myocardial fibrosis in cardiac diseases but has several limitations. T2 measurement may represent an alternative for fibrosis quantification at high magnetic field.
  
  
  METHODS
  A magnetic resonance imaging protocol including in vivo T2 measurements at 11.75 T was performed in 9 male C57BL/6J mice after 8 weeks of streptozotocin-induced diabetes and in 9 control mice. Programmed ventricular stimulation was performed in both groups. T2 measurements were compared with histologic quantification of fibrosis using picrosirius red staining.
  
  
  RESULTS
  Myocardial T2 was significantly lower in diabetic mice (13.8 ± 2.8 ms) than in controls (18.9 ± 2.3 ms, P < 0.001). There was a good correlation between T2 and fibrosis area obtained by histopathology (R = 0.947, P < 0.001). During programmed ventricular stimulation, 3 nonsustained ventricular tachycardias were induced in diabetic mice versus none in the control group.
  
  
  CONCLUSIONS
  The in vivo T2 relaxation time strongly correlated with myocardial fibrosis area assessed with histologic staining in diabetic mice.
authors.affiliation: Centre de Résonance Magnétique Biologique et Médicale-UMR 6612 CNRS, Université de la Méditerranée, Faculté de Médecine, Marseille, France. sithi.bun@gmail.com
authors.forename: Sok-Sithikun
authors.initials: SS
authors.lastname: Bun
authors.forename: Frank
authors.initials: F
authors.lastname: Kober
authors.forename: Alexis
authors.initials: A
authors.lastname: Jacquier
authors.forename: Leon
authors.initials: L
authors.lastname: Espinosa
authors.forename: Jérôme
authors.initials: J
authors.lastname: Kalifa
authors.forename: Marie-France
authors.initials: MF
authors.lastname: Bonzi
authors.forename: Francis
authors.initials: F
authors.lastname: Kopp
authors.forename: Nathalie
authors.initials: N
authors.lastname: Lalevee
authors.forename: Stephane
authors.initials: S
authors.lastname: Zaffran
authors.forename: Jean-Claude
authors.initials: JC
authors.lastname: Deharo
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Cozzone
authors.forename: Monique
authors.initials: M
authors.lastname: Bernard
mesh_terms: D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000139:chemically induced / Q000150:complications / Q000473:pathology*; D004719:Endomyocardial Fibrosis / Q000209:etiology / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013311:Streptozocin
chemical_list: D013311:Streptozocin