Contrast-enhanced magnetic resonance imaging of myocardium at risk: distinction between reversible and irreversible injury throughout infarct healing.

Published

Journal Article

OBJECTIVES: We sought to determine the relationship of delayed hyperenhancement by contrast magnetic resonance imaging (MRI) to viable and nonviable myocardium within the region at risk throughout infarct healing. BACKGROUND: The relationship of delayed MRI contrast enhancement patterns to injured but viable myocardium within the ischemic bed at risk has not been established. METHODS: We compared in vivo and ex vivo MRI contrast enhancement to histopathologic tissue sections encompassing the entire left ventricle in dogs (n = 24) subjected to infarction with (n = 12) and without (n = 12) reperfusion at 4 h, 1 day, 3 days, 10 days, 4 weeks and 8 weeks. In vivo MR imaging was performed 30 min after contrast injection. RESULTS: The sizes and shapes of in vivo myocardial regions of elevated image intensity (828+/-132% of remote) were the same as those observed ex vivo (241 slices, r = 0.99, bias = 0.05+/-1.6% of left ventricle [LV]). Comparison of ex vivo MRI to triphenyltetrazolim chloride-stained sections demonstrated that the spatial extent of hyperenhancement was the same as the spatial extent ofinfarction at every stage of healing (510 slices, lowest r = 0.95, largest bias = 1.7+/-2.9% of LV). Conversely, hyperenhanced regions were smaller than the ischemic bed at risk defined by fluorescent microparticles at every stage of healing (239 slices, 35+/-24% of risk region, p<0.001). Image intensities of viable myocardium within the risk region were the same as those of remote, normal myocardium (102+/-9% of remote, p = NS). CONCLUSIONS: Delayed contrast enhancement by MRI distinguishes between viable and nonviable regions within the myocardium at risk throughout infarct healing.

Full Text

Duke Authors

Cited Authors

  • Fieno, DS; Kim, RJ; Chen, EL; Lomasney, JW; Klocke, FJ; Judd, RM

Published Date

  • November 15, 2000

Published In

Volume / Issue

  • 36 / 6

Start / End Page

  • 1985 - 1991

PubMed ID

  • 11092675

Pubmed Central ID

  • 11092675

International Standard Serial Number (ISSN)

  • 0735-1097

Digital Object Identifier (DOI)

  • 10.1016/s0735-1097(00)00958-x

Language

  • eng

Conference Location

  • United States