title: Diffuse myocardial fibrosis evaluated by post-contrast t1 mapping correlates with left ventricular stiffness.
abstract: OBJECTIVE
  The purpose of this study was to use cardiac magnetic resonance (CMR) imaging and invasive left ventricular (LV) pressure-volume (PV) measurements to explore the relationship between diffuse myocardial fibrosis and indexes of diastolic performance in a cohort of cardiac transplant recipients.
  
  
  BACKGROUND
  The precise mechanism of LV diastolic dysfunction in the presence of myocardial fibrosis has not previously been established.
  
  
  METHODS
  We performed CMR with T1 mapping and obtained invasive LV PV measurements via a conductance catheter in 20 cardiac transplant recipients at the time of clinically-indicated coronary angiography.
  
  
  RESULTS
  Both post-contrast myocardial T1 time and extracellular volume fraction correlated with β, the load-independent passive LV stiffness constant (r = -0.71, p = 0.001, and r = 0.58, p = 0.04, respectively). After multivariate analysis, post-contrast myocardial T1 time remained the only independent predictor of β. No significant associations were observed between myocardial T1 time and τ, the active LV relaxation constant, or other load-dependent parameters of diastolic function.
  
  
  CONCLUSIONS
  Diffuse myocardial fibrosis, assessed by post-contrast myocardial T1 time, correlates with invasively-demonstrated LV stiffness in cardiac transplant recipients. In patients with increased diffuse myocardial fibrosis, abnormal passive ventricular stiffness is therefore likely to be a major contributor to diastolic dysfunction.
authors: Heart Centre, Alfred Hospital, Melbourne, Victoria, Australia; Baker IDI Heart and Diabetes Research Institute, Melbourne, Victoria, Australia.
authors: Andris H
authors: AH
authors: Ellims
authors: Heart Centre, Alfred Hospital, Melbourne, Victoria, Australia; Baker IDI Heart and Diabetes Research Institute, Melbourne, Victoria, Australia.
authors: James A
authors: JA
authors: Shaw
authors: Heart Centre, Alfred Hospital, Melbourne, Victoria, Australia; Baker IDI Heart and Diabetes Research Institute, Melbourne, Victoria, Australia.
authors: Dion
authors: D
authors: Stub
authors: Heart Centre, Alfred Hospital, Melbourne, Victoria, Australia; Baker IDI Heart and Diabetes Research Institute, Melbourne, Victoria, Australia.
authors: Leah M
authors: LM
authors: Iles
authors: Heart Centre, Alfred Hospital, Melbourne, Victoria, Australia; Baker IDI Heart and Diabetes Research Institute, Melbourne, Victoria, Australia.
authors: James L
authors: JL
authors: Hare
authors: GE Healthcare, Bethesda, Maryland.
authors: Glenn S
authors: GS
authors: Slavin
authors: Heart Centre, Alfred Hospital, Melbourne, Victoria, Australia; Baker IDI Heart and Diabetes Research Institute, Melbourne, Victoria, Australia.
authors: David M
authors: DM
authors: Kaye
authors: Heart Centre, Alfred Hospital, Melbourne, Victoria, Australia; Baker IDI Heart and Diabetes Research Institute, Melbourne, Victoria, Australia. Electronic address: andrew.taylor@bakeridi.edu.au.
authors: Andrew J
authors: AJ
authors: Taylor
mesh_terms: D000328:Adult; D000368:Aged; D018780:Body Surface Potential Mapping / Q000379:methods*; D015331:Cohort Studies; D003287:Contrast Media; D015150:Echocardiography, Doppler / Q000379:methods; D005260:Female; D005355:Fibrosis / Q000473:pathology; D019786:Gadolinium DTPA; D016027:Heart Transplantation / Q000009:adverse effects / Q000379:methods*; D006801:Humans; D019028:Magnetic Resonance Imaging, Cine / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000473:pathology*; D011446:Prospective Studies; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis / Q000209:etiology / Q000473:pathology*
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA
keywords: T(1) mapping; diastolic dysfunction; magnetic resonance imaging; myocardial fibrosis