Comparison of initial cell retention and clearance kinetics after subendocardial or subepicardial injections of endothelial progenitor cells in a canine myocardial infarction model

J Nucl Med. 2010 Mar;51(3):413-7. doi: 10.2967/jnumed.109.069732. Epub 2010 Feb 11.


Neither intravenous nor intracoronary routes provide targeted stem cell delivery to recently infarcted myocardium in sufficient quantities. Direct routes appear preferable. However, most prior studies have used epicardial injections, which are not practical for routine clinical use. The objective of this study was to compare cell retention and clearance kinetics between a subepicardial and a subendocardial technique.

Methods: We evaluated 7 dogs with each technique, using (111)In-tropolone-labeled endothelial progenitor cells and serial SPECT/CT for 15 d after injection.

Results: In vivo indium imaging demonstrated comparable degrees of retention: 57% +/- 15% for the subepicardial injections and 54% +/- 26% for the subendocardial injections. Clearance half-lives were also similar at 69 +/- 26 and 60 +/- 21 h, respectively.

Conclusion: This study demonstrates that subendocardial injections, clinically more practical, show clearance kinetics comparable to those of subepicardial injections and will facilitate the ultimate clinical use of this treatment modality.

Publication types

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

MeSH terms

  • Animals
  • Cell Differentiation
  • Disease Models, Animal
  • Dogs
  • Endocardium*
  • Endothelial Cells / cytology*
  • Endothelial Cells / transplantation
  • Female
  • Half-Life
  • Injections / methods*
  • Metabolic Clearance Rate
  • Myocardial Infarction / diagnostic imaging
  • Myocardial Infarction / metabolism
  • Myocardial Infarction / surgery*
  • Organometallic Compounds
  • Pericardium*
  • Stem Cell Transplantation*
  • Stem Cells / cytology
  • Stem Cells / metabolism*
  • Time Factors
  • Tomography, Emission-Computed, Single-Photon
  • Tropolone / analogs & derivatives


  • Organometallic Compounds
  • indium tris(tropolonate)
  • Tropolone