Mesenchymal stromal cells and ischemic heart disease: hitting the target?

A recent study by researchers from the Copenhagen University Hospital assessed the impact of marrow-derived mesenchymal stromal cell (MSC) administration in human patients with ischemic heart failure. Outcomes from this randomized, double-blind, placebo controlled trial, which were reported in the European Heart Journal in July of 2015 (1) indicate that intra-myocardial stem cell delivery is well-tolerated and yields measurable improvements in myocardial function. In this study patients receiving MSCs (n=40) or placebo (n=20) exhibited similar baseline characteristics before treatment, and their cardiac function was evaluated at 6 months post-treatment by magnetic resonance imaging (MRI) or computed tomography (CT). Importantly, the study achieved its primary endpoint of efficacy, which was a significant reduction in left ventricular end-systolic volume (LVESV) in the MSC treatment group (−7.6±13.2 mL; P=0.001). In contrast, the placebo treatment group showed no significant change in LVESV (5.4±12.5 mL; P=0.07) while the difference between treatment groups was also highly significant (P=0.001). MSC administration also yielded significant improvements in left ventricular enddiastolic volume (LVEDV), left ventricular ejection fraction (LVEF), systolic volume (SV), and cardiac output (CO) at 6 months post-treatment. None of these parameters were significantly altered in patients receiving placebo, and all but LVEDV differed significantly between treatment groups. MSC administration also resulted in a significant increase in left ventricular (LV) mass, end-systolic wall thickness, and reduced scar mass.