Regional matrix metalloproteinase activation correlates with microstructure diffusion tensor indices post myocardial infarction

Introduction Post myocardial infarction (MI) activated matrix metalloproteinases (MMPs) degrade the extracellular matrix (ECM) and alter the tissue microstructure (TMS). Diffusion Tensor MRI (DT-MRI) yields diffusivity and anisotropy indices that characterize the TMS. Our previous studies in pigs post-MI have showed that gross spatial and temporal changes in mean diffusivity () and fractional anisotropy (FA) correlate with MMP activation assessed with a 99 mTc-labeled radiotracer (RP805) targeted at activated MMPs.