title: Non-invasive assessment of experimental autoimmune myocarditis in rats using a 3 T clinical MRI scanner.
abstract: OBJECTIVE
  The aim of this study was to assess the use of a 3 T clinical cardiac magnetic resonance (CMR) scanner to detect injury to the heart in experimental autoimmune myocarditis (EAM).
  
  
  RESULTS
  The use of 3 T CMR for the detection of cardiac injury was assessed in EAM (n = 55) and control (n = 10) male Lewis rats. Animals were evaluated with serial CMR imaging studies, using a 3 T scanner, and with 2D echocardiography before, and at 2 and 5 weeks after EAM induction. By CMR, regional wall motion abnormalities were noted in seven out of eight rats with myocarditis 5 weeks after induction. Subsequently, the rats developed significant left ventricular (LV) dilatation, wall thickening, and pericardial effusion. Average LV systolic and diastolic volumes increased from 131 ± 10 to 257 ± 20 µL (P = 0.0008), and from 309 ± 14 to 412 ± 24 µL (P < 0.0001), and ejection fraction markedly deteriorated (from 58 ± 2 to 37 ± 5%; P = 0.0003). Areas of fibrosis were located by late gadolinium enhancement (LGE) CMR at the subepicardium, mainly within the anterior, lateral, and inferior walls. The extent and location of LGE were highly correlated (r = 0.94; P < 0.0001) with areas of myocardial fibrosis by histopathology, with 85% sensitivity and 86% specificity.
  
  
  CONCLUSIONS
  A clinical 3 T CMR scanner enables accurate detection, quantification, and monitoring of experimental myocarditis in rats, and could be used for translational research to study the pathophysiology of the disease and evaluate novel therapies.
authors: Tamman Cardiovascular Research Institute, Leviev Heart Center, Sheba Medical Center, Tel-Hashomer, Israel.
authors: Shunit
authors: S
authors: Rinkevich-Shop
authors: Eli
authors: E
authors: Konen
authors: Tammar
authors: T
authors: Kushnir
authors: Frederick H
authors: FH
authors: Epstein
authors: Natalie
authors: N
authors: Landa-Rouben
authors: Orly
authors: O
authors: Goitein
authors: Tamar
authors: T
authors: Ben Mordechai
authors: Micha S
authors: MS
authors: Feinberg
authors: Arnon
authors: A
authors: Afek
authors: Jonathan
authors: J
authors: Leor
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001327:Autoimmune Diseases / Q000175:diagnosis*; D001707:Biopsy, Needle; D004195:Disease Models, Animal; D015150:Echocardiography, Doppler / Q000379:methods; D021621:Imaging, Three-Dimensional; D007150:Immunohistochemistry; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D009205:Myocarditis / Q000175:diagnosis* / Q000276:immunology; D011897:Random Allocation; D051381:Rats; D011917:Rats, Inbred Lew; D012016:Reference Values
keywords: Cardiac MRI; Myocarditis; Remodelling