Reperfused rat myocardium subjected to various durations of ischemia: estimation of the distribution volume of contrast material with echo-planar MR imaging

Radiology. 2000 May;215(2):520-8. doi: 10.1148/radiology.215.2.r00ma38520.

Abstract

Purpose: To estimate and compare the fractional distribution volume (fDV) of gadodiamide injection and technetium 99m-diethylenetriaminepentaacetic acid (DTPA) in the reperfused myocardium of rat hearts subjected to various durations of ischemia.

Materials and methods: Magnetic resonance (MR) imaging and autoradiography were performed in rats subjected to 20, 30, 40, or 60 minutes of regional ischemia followed by 1 hour of reperfusion. The fDVs of gadodiamide injection and (99m)Tc-DTPA were measured and compared by using inversion-recovery echo-planar imaging and autoradiographic phosphor imaging, respectively.

Results: The mean fDV of both tracers (gadodiamide and (99m)Tc-DTPA) in normal myocardium was 18% +/- 1, whereas that in the entire area at risk increased significantly (P <.05) with 20, 30, 40, and 60 minutes of ischemia to 32% +/- 1, 57% +/- 4, 66% +/- 2, and 68% +/- 2, respectively. The fDV was significantly (P <.05) greater in the core of infarction-78% +/- 4, 89% +/- 5, and 88% +/- 5 with 30, 40, and 60 minutes of ischemia, respectively-than in the normal myocardium or in the area at risk.

Conclusion: The fDV of MR contrast material in the periinfarcted rim was significantly (P <. 05) greater than that in the normal myocardium, but significantly less than that in the core of infarcted myocardium.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Analysis of Variance
  • Animals
  • Autoradiography
  • Coloring Agents
  • Contrast Media / pharmacokinetics*
  • Echo-Planar Imaging*
  • Feasibility Studies
  • Gadolinium DTPA / pharmacokinetics*
  • Indoles
  • Magnetic Resonance Imaging
  • Microscopy, Electron
  • Myocardial Infarction / metabolism
  • Myocardial Infarction / pathology
  • Myocardial Ischemia / metabolism*
  • Myocardial Ischemia / pathology
  • Myocardial Reperfusion*
  • Myocardium / metabolism*
  • Myocardium / pathology
  • Myocardium / ultrastructure
  • Organometallic Compounds
  • Radiopharmaceuticals / pharmacokinetics
  • Rats
  • Rats, Sprague-Dawley
  • Technetium Tc 99m Pentetate / pharmacokinetics
  • Time Factors
  • Tissue Survival

Substances

  • Coloring Agents
  • Contrast Media
  • Indoles
  • Organometallic Compounds
  • Radiopharmaceuticals
  • copper phthalocyanine
  • Gadolinium DTPA
  • Technetium Tc 99m Pentetate