Objectives The objective is to perform a meta-analysis of clinical trials that investigated the effects of bone marrow cell (BMC) therapy on left ventricular (LV) function and LV remodelling in patients after acute myocardial infarction (AMI).

Background Intracoronary injection of BMCs in the acute phase of myocardial infarction has been proposed to replace cardiomyocytes lost and prevent deleterious pathological remodelling after myocardial infarction. Previously published trials have investigated the effects of cell therapy on LV function and remodelling in AMI patients. However, the sample size of these studies is small and the conclusions are inconsistent.

Methods Trials were identified in Cochrane Library, EMBASE, and PubMed databases, reviews, and reference lists of relevant papers. The weighted mean difference (WMD) was calculated for net changes in LV ejection fraction (LVEF) and LV end-diastolic volumes (LVEDV) by using random or fixed-effect models.

Results Ten randomised controlled trials (12 comparisons) with a total of 814 participants were included. In an overall pooled estimate, compared with the control group, BMCs therapy significantly improved the LVEF change from baseline to follow-up (WMD: 3.79%, 95% CI 2.4% to 5.7%, p<0.001). However, compared with the control group, stem cell therapy did not influence the LVEDV changes from baseline to follow-up (WMD: −1.76 ml, 95% CI −4.61 to 1.08 ml, p=0.233).

Conclusion This meta-analysis suggests that cell therapy improves left ventricular contractility, whereas has no effect on LV remodelling.