title: T1 and T2 mapping cardiovascular magnetic resonance imaging techniques reveal unapparent myocardial injury in patients with myocarditis.
abstract: BACKGROUND
  This study evaluated the ability of T1 and T2 mapping cardiovascular magnetic resonance (CMR) to detect myocardial injury in apparently normal myocardium of patients with myocarditis.
  
  
  METHODS
  We included 20 patients with "infarct-like" acute myocarditis who had typical focal myocardial lesions on late gadolinium enhancement (LGE) images as well as 20 healthy controls. The CMR protocol consisted of a standard myocarditis protocol which was combined with T1 (modified Look-Locker inversion recovery (MOLLI) with a 3(3)5 scheme and T2 mapping (hybrid gradient- and spin-echo multi-echo sequence, GraSE). First, LGE images were used to depict focal myocardial injury and apparently normal, remote myocardium. Second, native T1, T2 and ECV values were obtained in focal lesions but also in apparently normal myocardium. Third, native T1, T2 and ECV values ≥2 standard deviations above reference values obtained in healthy volunteers were used to quantify myocardial injury in patients with myocarditis.
  
  
  RESULTS
  Apparently normal myocardium had significantly higher median native T1 [1095 (1055-1148) ms] and ECV [34 (32-35) %] values compared to reference values from healthy volunteers, which were 1051 (1021-1064) ms (p < 0.01) and 26 (24-27) % (p < 0.0001). Furthermore, a nonsignificant increase in median myocardial T2 was detected in apparently normal myocardium of patients with myocarditis compared to healthy volunteers [59 (55-65) vs. 56 (54-60) ms; p = 0.18]. Consequently, the amount of myocardial injury was significantly larger on native T1 [48 (32-56) %; p < 0.01] and ECV maps [58 (50-66) %; p < 0.01] compared to LGE [14 (9-20) %].
  
  
  CONCLUSIONS
  Native T1 and ECV maps reveal hidden myocardial injury in normal appearing myocardium of patients with myocarditis. The amount of myocardial injury in myocarditis was underestimated by conventional LGE imaging.
authors.affiliation: Department of General and Interventional Cardiology, University Heart Center Hamburg, Hamburg, Germany. u.radunski@uke.de.
authors.forename: Ulf K
authors.initials: UK
authors.lastname: Radunski
authors.affiliation: Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
authors.forename: Gunnar K
authors.initials: GK
authors.lastname: Lund
authors.affiliation: Information Technology and Image Processing, University of Applied Sciences, Wedel, Germany.
authors.forename: Dennis
authors.initials: D
authors.lastname: Säring
authors.affiliation: Department of General and Interventional Cardiology, University Heart Center Hamburg, Hamburg, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Bohnen
authors.affiliation: Philips Research Germany, Hamburg, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Stehning
authors.affiliation: Philips Healthcare Germany, Hamburg, Germany.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Schnackenburg
authors.affiliation: Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
authors.forename: Maxim
authors.initials: M
authors.lastname: Avanesov
authors.affiliation: Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
authors.forename: Enver
authors.initials: E
authors.lastname: Tahir
authors.affiliation: Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
authors.forename: Gerhard
authors.initials: G
authors.lastname: Adam
authors.affiliation: Department of General and Interventional Cardiology, University Heart Center Hamburg, Hamburg, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Blankenberg
authors.affiliation: Department of General and Interventional Cardiology, University Heart Center Hamburg, Hamburg, Germany.
authors.forename: Kai
authors.initials: K
authors.lastname: Muellerleile
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D003287:Contrast Media; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D008536:Meglumine / Q000031:analogs & derivatives; D008875:Middle Aged; D009205:Myocarditis / Q000000981:diagnostic imaging* / Q000473:pathology; D009206:Myocardium / Q000473:pathology*; D009942:Organometallic Compounds; D011237:Predictive Value of Tests; D012720:Severity of Illness Index
chemical_list: D003287:Contrast Media; D009942:Organometallic Compounds; C064572:gadobenic acid; D008536:Meglumine
keywords: ECV imaging; Myocardial injury; Myocarditis; T1 mapping; T2 mapping