Normal and infarcted myocardium: differentiation with cellular uptake of manganese at MR imaging in a rat model

Radiology. 2000 Aug;216(2):524-30. doi: 10.1148/radiology.216.2.r00jl14524.


Purpose: To assess whether normal myocardium can be distinguished from infarction at magnetic resonance (MR) imaging with low doses of manganese dipyridoxyl diphosphate (Mn-DPDP).

Materials and methods: After 1-hour coronary arterial occlusion and 2-hour reperfusion, three groups of eight rats each were injected with 25, 50, or 100 micromol of Mn-DPDP per kilogram of body weight. The longitudinal relaxation rate (R1) in normal myocardium, reperfused infarction, and blood was repeatedly measured at inversion-recovery echo-planar imaging before and for 1 hour after the administration of contrast material. Afterward, several animals from each group were examined at high-spatial-resolution inversion-recovery spin-echo (SE) MR imaging.

Results: Manganese accumulated in normal myocardium but was cleared from reperfused infarction and blood. One hour after the administration of Mn-DPDP, R1 in normal myocardium (1.53 sec(-1) +/- 0.03, 1.73 sec(-1) +/- 0.03, and 1.94 sec(-1) +/- 0.02, respectively, for 25, 50, and 100 micromol/kg) was significantly (P <.05) faster than that of reperfused infarction (0.99 sec(-1) +/- 0.03, 1.11 sec(-1) +/- 0.03, and 1.48 sec(-1) +/- 0.06). Normal myocardium appeared hyperintense on T1-weighted inversion-recovery SE MR images and was clearly distinguishable from reperfused infarction.

Conclusion: Mn-DPDP-enhanced inversion-recovery echo-planar and SE MR images demonstrated retention of manganese in normal myocardium and clearance of manganese from infarction. Mn-DPDP has characteristics similar to those of widely used thallium and may be useful in the assessment of myocardial viability at MR imaging.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Analysis of Variance
  • Animals
  • Contrast Media*
  • Coronary Disease / complications
  • Disease Models, Animal
  • Dose-Response Relationship, Drug
  • Echo-Planar Imaging
  • Edetic Acid / administration & dosage
  • Edetic Acid / analogs & derivatives*
  • Edetic Acid / blood
  • Female
  • Follow-Up Studies
  • Magnetic Resonance Imaging / methods*
  • Manganese / administration & dosage
  • Manganese / blood
  • Manganese / pharmacokinetics*
  • Metabolic Clearance Rate
  • Myocardial Infarction / etiology
  • Myocardial Infarction / metabolism*
  • Myocardial Reperfusion
  • Myocardium / metabolism*
  • Pyridoxal Phosphate / administration & dosage
  • Pyridoxal Phosphate / analogs & derivatives*
  • Pyridoxal Phosphate / blood
  • Rats
  • Rats, Sprague-Dawley


  • Contrast Media
  • Manganese
  • Pyridoxal Phosphate
  • Edetic Acid
  • N,N'-bis(pyridoxal-5-phosphate)ethylenediamine-N,N'-diacetic acid