MRI detects myocardial iron in the human heart.
Iron-induced cardiac dysfunction is a leading cause of death in transfusion-dependent anemia. MRI relaxation rates R2(1/T2) and R2*(1/T2*) accurately predict liver iron concentration, but their ability to predict cardiac iron has been challenged by some investigators. Studies in animal models support similar R2 and R2* behavior with heart and liver iron, but human studies are lacking. To determine the relationship between MRI relaxivities and cardiac iron, regional variations in R2 and R2* were compared with iron distribution in one freshly deceased, unfixed, iron-loaded heart. R2 and R2* were proportionally related to regional iron concentrations and highly concordant with one another within the interventricular septum. A comparison of postmortem and in vitro measurements supports the notion that cardiac R2* should be assessed in the septum rather than the whole heart. These data, along with measurements from controls, provide bounds on MRI-iron calibration curves in human heart and further support the clinical use of cardiac MRI in iron-overload syndromes.
Ghugre
Nilesh R
NR
Division of Cardiology, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, California 90027-0034, USA.
Enriquez
Cathleen M
CM
Gonzalez
Ignacio
I
Nelson
Marvin D
MD
Coates
Thomas D
TD
Wood
John C
JC
D000328:Adult; D002102:Cadaver; D006331:Heart Diseases / Q000175:diagnosis* / Q000378:metabolism*; D006801:Humans; D007501:Iron / Q000032:analysis*; D019189:Iron Metabolism Disorders / Q000175:diagnosis* / Q000378:metabolism*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014018:Tissue Distribution; D017086:beta-Thalassemia / Q000175:diagnosis / Q000378:metabolism
D007501:Iron