Assessment of cardiac iron by MRI susceptometry and R2* in patients with thalassemia

Magn Reson Imaging. 2010 Apr;28(3):363-71. doi: 10.1016/j.mri.2009.12.001. Epub 2010 Jan 12.

Abstract

A magnetic resonance imaging cardiac magnetic susceptometry (MRI-CS) technique for assessing cardiac tissue iron concentration based on phase mapping was developed. Normal control subjects (n=9) and thalassemia patients (n=13) receiving long-term blood transfusion therapy underwent MRI-CS and MRI measurements of the cardiac relaxation rate R2*. Using MRI-CS, subepicardium and subendocardium iron concentrations were quantified exploiting the hemosiderin/ferritin iron specific magnetic susceptibility. The average of subepicardium and subendocardium iron concentrations and R2* of the septum were found to be strongly correlated (r=0.96, P<.0001), and linear regression analysis yielded CIC (microg Fe/g(wet tissue))=(6.4+/-0.4).R2* (septum) (s(-1)) - (120+/-40). The results demonstrated that septal R2* indeed measures cardiac iron level.

Keywords: MRI; R2*; heart; iron overload; magnetic susceptibility; thalassemia.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adult
  • Algorithms*
  • Biomarkers / analysis
  • Female
  • Humans
  • Image Enhancement / methods
  • Image Interpretation, Computer-Assisted / methods*
  • Iron / analysis*
  • Magnetic Resonance Imaging / methods*
  • Male
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Thalassemia / diagnosis*
  • Thalassemia / metabolism*
  • Young Adult

Substances

  • Biomarkers
  • Iron