title: T(1) mapping for the diagnosis of acute myocarditis using CMR: comparison to T2-weighted and late gadolinium enhanced imaging.
abstract: OBJECTIVE
  This study sought to test the diagnostic performance of native T1 mapping in acute myocarditis compared with cardiac magnetic resonance (CMR) techniques such as dark-blood T2-weighted (T2W)-CMR, bright-blood T2W-CMR, and late gadolinium enhancement (LGE) imaging.
  
  
  BACKGROUND
  The diagnosis of acute myocarditis on CMR often requires multiple techniques, including T2W, early gadolinium enhancement, and LGE imaging. Novel techniques such as T1 mapping and bright-blood T2W-CMR are also sensitive to changes in free water content. We hypothesized that these techniques can serve as new and potentially superior diagnostic criteria for myocarditis.
  
  
  METHODS
  We investigated 50 patients with suspected acute myocarditis (age 42 ± 16 years; 22% women) and 45 controls (age 42 ± 14 years; 22% women). CMR at 1.5-T (median 3 days from presentation) included: 1) dark-blood T2W-CMR (short-tau inversion recovery); 2) bright-blood T2W-CMR (acquisition for cardiac unified T2 edema); 3) native T1 mapping (shortened modified look-locker inversion recovery); and 4) LGE. Image analysis included: 1) global T2 signal intensity ratio of myocardium compared with skeletal muscle; 2) myocardial T1 relaxation times; and 3) areas of LGE.
  
  
  RESULTS
  Compared with controls, patients had significantly higher global T2 signal intensity ratios by dark-blood T2W-CMR (1.73 ± 0.27 vs. 1.56 ± 0.15, p < 0.01), bright-blood T2W-CMR (2.02 ± 0.33 vs. 1.84 ± 0.17, p < 0.01), and mean myocardial T1 (1,010 ± 65 ms vs. 941 ± 18 ms, p < 0.01). Receiver-operating characteristic analysis showed clear differences in diagnostic performance. The areas under the curve for each method were: T1 mapping (0.95), LGE (0.96), dark-blood T2 (0.78), and bright-blood T2 (0.76). A T1 cutoff of 990 ms had a sensitivity, specificity, and diagnostic accuracy of 90%, 91%, and 91%, respectively.
  
  
  CONCLUSIONS
  Native T1 mapping as a novel criterion for the detection of acute myocarditis showed excellent and superior diagnostic performance compared with T2W-CMR. It also has a higher sensitivity compared with T2W and LGE techniques, which may be especially useful in detecting subtle focal disease and when gadolinium contrast imaging is not feasible.
authors.affiliation: Department of Cardiovascular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom.
authors.forename: Vanessa M
authors.initials: VM
authors.lastname: Ferreira
authors.affiliation: Department of Cardiovascular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom.
authors.forename: Stefan K
authors.initials: SK
authors.lastname: Piechnik
authors.affiliation: Department of Cardiovascular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom.
authors.forename: Erica
authors.initials: E
authors.lastname: Dall'Armellina
authors.affiliation: Department of Cardiovascular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom.
authors.forename: Theodoros D
authors.initials: TD
authors.lastname: Karamitsos
authors.affiliation: Department of Cardiovascular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom.
authors.forename: Jane M
authors.initials: JM
authors.lastname: Francis
authors.affiliation: Department of Cardiovascular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom.
authors.forename: Ntobeko
authors.initials: N
authors.lastname: Ntusi
authors.affiliation: Department of Cardiovascular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom.
authors.forename: Cameron
authors.initials: C
authors.lastname: Holloway
authors.affiliation: Department of Cardiovascular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom.
authors.forename: Robin P
authors.initials: RP
authors.lastname: Choudhury
authors.affiliation: Department of Cardiology, Milton Keynes NHS Hospital Foundation Trust, Milton Keynes, United Kingdom.
authors.forename: Attila
authors.initials: A
authors.lastname: Kardos
authors.affiliation: Department of Cardiovascular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom.
authors.forename: Matthew D
authors.initials: MD
authors.lastname: Robson
authors.affiliation: Stephenson Cardiovascular MR Centre, Libin Cardiovascular Institute of Alberta, Calgary, Alberta, Canada; Department of Cardiology, Université de Montréal, Montréal, Quebec, Canada.
authors.forename: Matthias G
authors.initials: MG
authors.lastname: Friedrich
authors.affiliation: Department of Cardiovascular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom. Electronic address: stefan.neubauer@cardiov.ox.ac.uk.
authors.forename: Stefan
authors.initials: S
authors.lastname: Neubauer
mesh_terms: D000208:Acute Disease; D000328:Adult; D016022:Case-Control Studies; D003287:Contrast Media; D004489:Edema, Cardiac / Q000175:diagnosis; D004739:England; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008875:Middle Aged; D009205:Myocarditis / Q000175:diagnosis*; D011237:Predictive Value of Tests; D011446:Prospective Studies
chemical_list: D003287:Contrast Media; C064925:gadodiamide; D019786:Gadolinium DTPA
keywords: AUC; CMR; EGE; EMB; LGE; PPV; ROC; SI; STIR; ShMOLLI; T(1) mapping; T(2)-weighted; T(2)-weighted CMR; T2W; area under the curve; cardiac magnetic resonance; early gadolinium enhancement; endomyocardial biopsy; late gadolinium enhancement; myocarditis; positive predictive value; receiver-operating characteristic; short-tau inversion recovery; shortened modified look-locker inversion recovery; signal intensity