European Radiology

, Volume 16, Issue 4, pp 827–836

Scarred myocardium imposes additional burden on remote viable myocardium despite a reduction in the extent of area with late contrast MR enhancement

  • Maythem Saeed
  • Randall J. Lee
  • Oliver Weber
  • Loi Do
  • Alastair Martin
  • Philip Ursell
  • David Saloner
  • Charles B. Higgins
Experimental

DOI: 10.1007/s00330-005-0052-x

Cite this article as:
Saeed, M., Lee, R.J., Weber, O. et al. Eur Radiol (2006) 16: 827. doi:10.1007/s00330-005-0052-x

Abstract

Magnetic resonance imaging (MRI) can simultaneously detect and quantify myocardial dysfunction and shrinkage in contrast-enhanced areas postinfarction. This ability permits the investigation of our hypothesis that transformation of infracted myocardium to scarred tissue imposes additional burdens on peri-infarcted and remote myocardium. Pigs (n=8) were subjected to reperfused infarction. Gd-DOTA-enhanced inversion recovery gradient echo sequence (IR-GRE) imaging was performed 3 days and 8 weeks postinfarction. Global and regional left ventricular (LV) function was evaluated by cine MRI. Triphenyltetrazolium chloride (TTC) stain was used to delineate infarction while hematoxylin and eosin (H & E) and Masson’s trichrome stains were used to characterize remodeled myocardium. Late contrast-enhanced MRIs showed a decrease in the extent of enhanced areas from 17±2% at 3 days to13±1% LV mass at 8 weeks. TTC infarction size was 12±1% LV mass. Cine MRIs showed expansion in dysfunctional area due to unfavorable remodeling, ischemia, or strain. Ejection fraction was reduced in association with increased end-diastolic and end-systolic volumes. Scarred myocardium contained collagen fibers and remodeled thick-walled vessels embedded in collagen. Sequential MRI showed greater LV dysfunction despite the shrinkage in extent of enhanced areas 2 months postinfarction. The integration of late enhancement and cine MRI incorporates anatomical and functional evaluation of remodeled hearts.

Keywords

Myocardial infarctionCardiac functionMagnetic resonance imaging (MRI)MR contrast mediaLeft ventricular remodeling

Copyright information

© Springer-Verlag 2005

Authors and Affiliations

  • Maythem Saeed
    • 1
  • Randall J. Lee
    • 2
  • Oliver Weber
    • 1
  • Loi Do
    • 1
  • Alastair Martin
    • 1
  • Philip Ursell
    • 3
  • David Saloner
    • 1
  • Charles B. Higgins
    • 1
  1. 1.Department of RadiologyUniversity of CaliforniaSan FranciscoUSA
  2. 2.Department of MedicineUniversity of CaliforniaSan FranciscoUSA
  3. 3.Department of PathologyUniversity of CaliforniaSan FranciscoUSA