Myocardial strain in sub-acute peri-infarct myocardium

Academic Article

Abstract

  • Purpose: In the absence of additional ischemic insults, the peri-infarct region surrounding the infarct myocardium can recover function. T2 weighted MRI signal is sensitive to edema and used to detect peri-infarct, salvageable myocardium. The main purpose of this study was to investigate the alterations in myocardial strain in the peri-infarct myocardium as compared to normal and infarct myocardium. Materials and methods: Comprehensive MRI of the myocardium was performed in five pigs 6-7 days following coronary artery occlusion-reperfusion myocardial injury. MRI included tagged cine images for myocardial strain, T2weighted (T2w)-images and late gadolinium enhancement (LGE) for assessing myocardial viability. Automated signal intensity thresholds were used to define tissue edema and myocardial infarct. Maximum-shortening strains were analyzed in the infarct, peri-infarct and normal myocardial sectors. The results were correlated with triphenyltetrazolium-chloride (TTC) and hemotoxylin-eosin stained tissue images. Results: We found an excellent correlation of LGE with TTC (r =0.94, P < 0.05). T2w-images markedly overestimated the infarct size (25 ± 3%). Both the healthy and peri-infarct myocardial sectors had higher myocardial strain than infarct myocardial sectors (P < 0.05). Clear demarcation between infarct and non-infarct myocardium was noted on histology. Conclusion: Peri-infarct myocardium continues to demonstrate T2 signal enhancement to at least 7 days, but this region has preserved mechanical function. T2-weighted imaging and myocardial strain measurements provide complementary information and both may be useful for characterization of the peri-infarct myocardium. © Springer Science+Business Media, B.V. 2008.
  • Digital Object Identifier (doi)

    Pubmed Id

  • 8893579
  • Author List

  • Ruzsics B; Surányi P; Kiss P; Brott BC; Litovsky S; Denney TS; Aban I; Lloyd SG; Simor T; Elgavish GA
  • Start Page

  • 151
  • End Page

  • 159
  • Volume

  • 25
  • Issue

  • 2