Major Cardiovascular Events after Bone Marrow Mononuclear Cell Transplantation Following Acute Myocardial Infarction: A Meta-Analysis of Randomized Controlled Trials

Abstract The effect of bone marrow-derived mononuclear cells (BM-MNCs) after acute myocardial infarction (AMI) on myocardial function indices such as ejection fraction (LVEF) has been widely studied. However, the effect of this intervention on major cardiovascular events (MACE) was not the principal purpose of most investigations and its role is unclear. The aim of this study was to investigate the possible long-term clinical efficacy of BM-MNCs on MACE after AMI. A comprehensive search was conducted through electronic databases for potentially eligible randomized trials investigating the impact of BM-MNC therapy following acute MI on clinical outcomes. Risk of bias assessment of the eligible studies was done using the Cochrane Collaboration’s tool. Initial database search found 1540 records and 23 clinical trials with a total of 2286 participants considered eligible for meta-analysis. Injection of BM-MNCs was associated with lower risk of composite end point of hospitalization for heart failure (CHF), re-infarction, and cardiac-related mortality (88/1112 vs 111/787, p<0.001, RR=0.601, 95% CI=0.462 to 0.781). This effect was derived from both reduction of CHF (46/1152 vs 60/807, p=0.002, RR=0.549, 95% CI=0.379 to 0.795, I2=0.00%) and re-infarction rate ((24/1160 vs. 30/750, p=0.03, RR=0.580, 95% CI=0.354 to 0.949), but not cardiac-related mortality ((29/1291 vs. 31/846, p=0.208, RR=0.735, 95% CI=0.456 to 1.187, I2=0.00%) This is the first meta-analysis focused on the cardiovascular outcomes of stem cell therapy after AMI and it revealed that transplantation of BM-MNCs may reduce hospitalization for heart failure but not cardiovascular mortality.