Conclusions
Dual-modality imaging has the unique ability to monitor cell delivery, survival status, graft morphology, and impact on post-myocardial infarction remodeling.
Methods
Murine embryonic stem cells (0.3 million) were double-labeled with Fluc and superparamagnetic iron oxide particles and injected into the infarct border zone of athymic rat hearts. BLI and MRI were performed serially up to 2 months after injection, followed by immunohistochemistry.
Results
Dual-modality imaging was able to verify the initial intramyocardial delivery of the cells and their survival status. Over time, BLI signal increased in seven of nine hearts and disappeared in the other two hearts. The divergence of BLI signal over time was supported by MRI findings. Left ventricular ejection fraction and fractional shortening estimated by MRI suggested that cell engraftment mediated a positive impact on post-myocardial infarction remodeling. Two months after intramyocardial injection, superparamagnetic iron oxide-associated signals facilitated the localization of the injection site. Conclusions: Dual-modality imaging has the unique ability to monitor cell delivery, survival status, graft morphology, and impact on post-myocardial infarction remodeling.