title: Myocardial T1 maps reflect histological findings in acute and chronic stages of myocarditis in a rat model.
abstract: BACKGROUND
  Cardiovascular magnetic resonance offers both diagnostic and prognostic information in myocarditis. Using an established animal model of myocarditis, the aim of this study was to measure myocardial T1 before the onset, in the acute and in the chronic phases of the disease and to compare its course with histological and immunohistochemistry findings.
  
  
  METHODS
  Male young Lewis rats were immunized with 0.25 mg porcine myocardial myosin into the rear footpads on day 0. Native and contrast-enhanced ECG-triggered cardiac MRI examinations were performed before immunization on day 0 and on days 14, 21 and 35. Left ventricular function, pre- and post- contrast T1 parameters and LGE images were assessed using Small animal look-locker inversion recovery (SALLI). For each of the indicated time points a minimum of 4 rats were randomly sacrificed for pathological investigations including conventional histology (HE and Sirius-Red staining) and immunohistochemistry (CD 68) investigations.
  
  
  RESULTS
  All immunized rats developed myocarditis (morbidity 100%). Histologically we observed increased wall thickness with biventricular macrophage-rich mixed inflammatory infiltrates. All rats with a histologically severe myocarditis showed increased native T1 and decreased post-contrast T1 of the myocardium.
  
  
  CONCLUSIONS
  The assessment of native T1 and post-contrast T1 allows accurate differentiation between healthy myocardium and myocardium with inflammation and also between the acute and chronic phases of the disease.
authors.affiliation: Internal Medicine/Cardiology, Deutsches Herzzentrum Berlin, Augustenburger Platz 1, 13353, Berlin, Germany. jeuthe@dhzb.de.
authors.forename: Sarah
authors.initials: S
authors.lastname: Jeuthe
authors.affiliation: Cardiovascular Pathology, Cardiothoracic and Vascular Surgery, Deutsches Herzzentrum Berlin, Berlin, Germany.
authors.forename: Katharina
authors.initials: K
authors.lastname: Wassilew
authors.affiliation: Congenital Heart Disease and Pediatric Cardiology, Deutsches Herzzentrum Berlin, Berlin, Germany.
authors.forename: Darach
authors.initials: D
authors.lastname: O H-Ici
authors.affiliation: Congenital Heart Disease and Pediatric Cardiology, Deutsches Herzzentrum Berlin, Berlin, Germany.
authors.forename: Tiago Ferreira
authors.initials: TF
authors.lastname: da Silva
authors.affiliation: Congenital Heart Disease and Pediatric Cardiology, Deutsches Herzzentrum Berlin, Berlin, Germany.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Münch
authors.affiliation: Congenital Heart Disease and Pediatric Cardiology, Deutsches Herzzentrum Berlin, Berlin, Germany.
authors.forename: Felix
authors.initials: F
authors.lastname: Berger
authors.affiliation: Congenital Heart Disease and Pediatric Cardiology, Deutsches Herzzentrum Berlin, Berlin, Germany.
authors.forename: Titus
authors.initials: T
authors.lastname: Kuehne
authors.affiliation: Internal Medicine/Cardiology, Deutsches Herzzentrum Berlin, Augustenburger Platz 1, 13353, Berlin, Germany.
authors.forename: Burkert
authors.initials: B
authors.lastname: Pieske
authors.affiliation: Internal Medicine/Cardiology, Deutsches Herzzentrum Berlin, Augustenburger Platz 1, 13353, Berlin, Germany.
authors.forename: Daniel R
authors.initials: DR
authors.lastname: Messroghli
mesh_terms: D000208:Acute Disease; D000818:Animals; D015703:Antigens, CD / Q000276:immunology; D015214:Antigens, Differentiation, Myelomonocytic / Q000276:immunology; D001327:Autoimmune Diseases / Q000139:chemically induced / Q000276:immunology / Q000473:pathology* / Q000503:physiopathology; D002311:Cardiomyopathy, Dilated / Q000139:chemically induced / Q000276:immunology / Q000473:pathology* / Q000503:physiopathology; D002908:Chronic Disease; D004195:Disease Models, Animal; D007150:Immunohistochemistry; D008279:Magnetic Resonance Imaging; D008297:Male; D009205:Myocarditis / Q000139:chemically induced / Q000276:immunology / Q000473:pathology* / Q000503:physiopathology; D009206:Myocardium / Q000276:immunology / Q000473:pathology*; D009218:Myosins; D011237:Predictive Value of Tests; D011917:Rats, Inbred Lew; D013997:Time Factors; D016277:Ventricular Function, Left; D000097382:CD68 Molecule
chemical_list: D015703:Antigens, CD; D015214:Antigens, Differentiation, Myelomonocytic; D009218:Myosins; C539355:CD68 protein, rat; D000097382:CD68 Molecule
keywords: Autoimmune myocarditis; Cardiovascular magnetic resonance; Dilated cardiomyopathy; Lewis rat; T1 mapping