Abstract 2242: Infarct Size Reduction Correlates with Increaed Contractility after Treatment with Allogeneic Mesenchymal Stem Cells
Introduction: Functional myocardial regeneration in ischemic cardiomyopathy is the ultimate goal of cell based therapy. Previous work has shown that allogeneic Mesenchymal Stem Cells (aMSCs) are capable or reducing the amount of measured scar, however, the potential of the newly generated myocardium has yet to be determined. We hypothesized that, in conjunction with infarct size reduction, regional wall motion would increase, and the values would have a correlative relationship.
Methods and Results: Nine female Gottingen swine underwent chronic myocardial infarction. Twelve weeks later they were assigned to receive catheter injection (Stilleto, Boston Scientific) of aMSCs (Osiris Therapeutics, n = 6) or placebo (n = 3). CMRI was performed at pre-injection and 1, 4, 8, and 12 week post-injection time points, during which delayed enhancement and tagged images were acquired. Comparison of the baseline pre-injection and 12 week post-injection data yielded a significant improvement in peak Eulerian circumferential shortening (Ecc) in the border zone (8.02 ± 2.36%, p < .018) from baseline (−7.62 ± 1.83%) and decrease in infarction size (4.26 ± 1.11%, p < .001) from baseline (19.05 ± 0.47%). The infarct size reduction was then plotted against the improvement in Ecc and was shown to have a high degree of correlation (R2 = .90).
Conclusion: The repair potential of aMSCs is clearly indicated by these data. Not only do aMSCs heal the myocardium by reducing the size of the infarct region, but they replace scar tissue with functional myocardium. The extent of repair is highly correlated with functional improvement. This provides a significant benefit model for current and future clinical trials.