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To evaluate contrast accumulation in left ventricular (LV) myocardium after manganese dipyridoxyl-diphosphate (MnDPDP) administration in patients with recent first time myocardial infarction.MnDPDP (5 μmol/kg) was administered to 10 patients with recent myocardial infarction (three to 12 weeks). One slice of interest (SOI) likely to traverse the infarction was chosen, and sectorial pre- and postcontrast longitudinal relaxivity rates (R1) and signal changes during infusion were estimated with a fast gradient echo sequence. LV volume and wall thickening were measured in short-axis cine recordings. Infarct localization from R1 and wall thickening data were compared by vector analyses.Reduced wall thickening was associated with reduced precontrast R1 and reduced contrast enhancement. Both remote and infarcted regions showed rapid initial contrast accumulation. In remote regions, this was followed by a continuing slow increase. Mean precontrast R1 was 0.87 ± 0.06 second–1 in infarcted regions and 0.96 ± 0.03 second–1 in remote regions (P < 0.001). Mean R1 change over one hour was 0.24 ± 0.07 second–1 in infarcted regions and 0.38 ± 0.03 second–1 in remote regions (P < 0.0001).Remote regions showed larger increases in R1 than infarcted regions. This is most likely due to selective and slow Mn accumulation in viable myocytes.