Figure 2

Post-mortem PET/MRI images from subject with permanent LAD occlusion imaged 7 days post MI. The images demonsrate both enhanced Gd-DTPA and FDG uptake surrounding a large central zone of microvascular obstruction (MO), suggesting minimal inflammatory cell activity in that region. However, analysis of the ex vivo tissue demonstrates a dissociation between Indium and FDG concentrations in tissue obtained from the MO zone. In some samples, Indium levels were up to 7 times higher, suggesting penetration of the labeled white blood cells injected 24 hours earlier, but minimal FDG following a single bolus injection. Therefore, FDG imaging may signficantly underestimate the degree and extent of inflammatory cell activity in the setting of MO.