Martin Ugander1, Marcus Y Chen1, Billy Chen1, Li-Yueh Hsu1, Peter Kellman1, Andrew E Arai1
1National Heart, Lung and
Blood Institute, National Institutes of Health,
The myocardial extracellular volume fraction (ECV) can by quantified by MR. However, independent validation is lacking. We performed ECV imaging by MR (1.5T) and CT (320 channel) in experimental acute myocardial infarction. ECV was quantified using hematocrit and T1 or Hounsfield unit quantification in tissue and blood before and after Gd-DTPA or iodinated contrast injection for MR and CT, respectively. ECV in remote, infarcted and peri-infarction myocardium by CT and MR correlated (R2=0.76, p<0.001, y=0.92x+0.08, MR bias 4.78.3 percentage points, n=17 measures in 6 dogs). CT provides independent validation that MR can be used to quantitatively image myocardial ECV.