Abstract 12019: Durable Infarct Size Reduction Due to Allogeneic Mesenchymal Stem Cell Therapy Regulates Whole-Chamber Left Ventricular Remodeling
Background: Myocardial infarction (MI) leads to left ventricular remodeling, characterized by progressive chamber enlargement and geometric change from an elliptical to a spherical configuration. As intramyocardial injection of mesenchymal stem cells (MSCs) have shown favorable effects on remodeling in chronic ischemic cardiomyopathy (ICM), we tested the hypothesis that allogeneic MSC therapy reverses ventricular remodeling through scar size reduction in swine with ICM.
Methods: Gottingen swine (n=12) underwent LAD MI at baseline. At 3 months post-MI, animals received either catheter-based intramyocardial allogeneic MSC injection (n=6) or sham LV catheterization without injection (n=6). Swine were followed with serial cardiac magnetic resonance imaging for 9 months to assess structural and functional changes of the LV.
Results: All animals survived the entire duration of the study. MSC treated animals had a sustainable 25% reduction in infarct size at 6 months post-injection and control animals had unchanged infarct size (p<0.05). Scar size reduction in MSC treated animals was evident at 3 months post-injection and lead to later reverse remodeling at 6 months post-injection, while control animals had progressive LV dilatation (Figure 1). Changes in scar size correlated with changes in EDV (r=0.68, p<0.05) and ESV (r=0.77, p<0.01) at 6 months post-injection. Furthermore, the LV of MSC treated animals were restored to a more natural elliptical configuration as measured by sphericity index (p<0.01). This reverse remodeling with MSC therapy was accompanied by improved ejection fraction compared to persistently depressed cardiac function in control animals (p<0.0001).
Conclusion: Intramyocardial injection of allogeneic MSCs reverses ventricular remodeling in ischemic cardiomyopathy through durable scar size reduction.
- © 2012 by American Heart Association, Inc.