title: T1 and T2 mapping for early diagnosis of dilated non-ischaemic cardiomyopathy in middle-aged patients and differentiation from normal physiological adaptation.
abstract: OBJECTIVE
  The differential diagnosis of patients with early non-ischaemic dilated cardiomyopathy (DCM) and those with physiological adaptation to exercise ('athlete's heart') may be difficult as many of the morphological adaptations are shared in the two conditions. Increased physical fitness is becoming more common in later adulthood, a group in whom there may be even more diagnostic difficulty. We hypothesized that tissue characterization using cardiovascular magnetic resonance (CMR) T1 and T2 mapping would be able to differentiate between patients with left ventricular (LV) dilatation due to early DCM and exercisers.
  
  
  RESULTS
  Fifty-eight middle-aged males [21 healthy controls, 21 males with a history of aerobic exercise and LV ejection fraction (LVEF) 45-55%, and 16 patients with DCM and LVEF 45-55%] underwent a CMR protocol including T1 and T2 mapping and calculation of extracellular volume (ECV) using a 1.5 T MRI scanner. Native T1, ECV, and T2 relaxation times were significantly increased in DCM patients compared with controls (native T1 1017 ± 42 vs. 952 ± 31 ms, P < 0.001; ECV 31.2 ± 4.1 vs. 26.2 ± 2.9%, P = 0.003; T2 55.9 ± 4.4 vs. 52.9 ± 3.3 ms, P = 0.05) and exercisers (native T1 957 ± 32 ms, P < 0.001; ECV 26.3 ± 3.6%, P = 0.004; T2 52.8 ± 3.2 ms, P = 0.042). Using multivariable logistic regression, native T1 gave the best differentiation between exercisers and sedentary patients with early DCM (area under the curve 0.91).
  
  
  CONCLUSIONS
  T1 and T2 mapping are potentially useful tools for differentiating between athlete's heart and patients with early DCM, and could be used whenever differentiation between these two phenotypes is inconclusive using standard imaging techniques.
authors.affiliation: BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow G12 8TA, UK ifyrmordi@doctors.org.uk.
authors.forename: Ify
authors.initials: I
authors.lastname: Mordi
authors.affiliation: BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow G12 8TA, UK.
authors.forename: David
authors.initials: D
authors.lastname: Carrick
authors.affiliation: Harrington Heart and Vascular Institute, University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, OH, USA.
authors.forename: Hiram
authors.initials: H
authors.lastname: Bezerra
authors.affiliation: BHF Glasgow Cardiovascular Research Centre, Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow G12 8TA, UK.
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Tzemos
mesh_terms: D000222:Adaptation, Physiological; D000704:Analysis of Variance; D002311:Cardiomyopathy, Dilated / Q000000981:diagnostic imaging* / Q000503:physiopathology; D016022:Case-Control Studies; D042241:Early Diagnosis; D017079:Exercise Tolerance / Q000502:physiology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D017202:Myocardial Ischemia; D011237:Predictive Value of Tests; D011379:Prognosis; D012016:Reference Values; D018570:Risk Assessment; D012720:Severity of Illness Index; D013318:Stroke Volume / Q000502:physiology*; D016277:Ventricular Function, Left / Q000502:physiology
keywords: Athletes; Cardiovascular magnetic resonance; Dilated cardiomyopathy; T1 mapping; T2 mapping