Autologous bone marrow mononuclear stem cells for acute myocardial infarction: is it only about time?

Abstract

This editorial refers to ‘A randomized double-blind controlled study of early intracoronary autologous bone marrow cell infusion in acute myocardial infarction: the REGENERATE-AMI clinical trial’[†][1], by F. Choudry et al ., on page 256. In 2002, Strauer et al .1 reported the results of the first phase I study testing the safety of intracoronary (IC) administration of autologous bone marrow mononuclear stem cells (BMMSCs) for acute myocardial infarction (AMI). Since then, we have seen a series of trials using mixed cell types with heterogeneous designs in terms of both the number and the timing of BMMSCs administration that have yielded conflicting results2 ( Figure 1 ). For example, Nowbar et al .3 found no beneficial effect on left ventricular ejection fraction (LVEF) when analysing BMMSCs trials without any discrepancies, while a meta-analysis by Afzal et al .4 (48 studies; 2602 patients) showed an improvement in both LVEF (+2.92%) and infarct size (−2.25%), as well as remodelling. Taken as a whole, these contradictory findings have left the general cardiology community somewhat indifferent and have arguably shrouded the field of BMMSC AMI research in a dark fog from which it has yet to emerge. Figure 1 Factors affecting the bone marrow cells effect on cardiac recovery after acute myocardial infarction. LV, left ventricle; MACE, major adverse cardiac events. In this issue of the journal, Choudry et al .5 present the results of the REGENERATE-AMI trial, evaluating the effect of IC autologous BMMSCs on left ventricular (LV) function when delivered within 24 h of successful reperfusion therapy. While REGENERATE-AMI did not meet its primary endpoint, there is much potential value in trying to place this … [1]: #fn-2