Effects of stem cell therapy on left ventricular remodeling after acute myocardial infarction: A meta-analysis

Objectives: The objective was to perform a meta-analysis of clinical trials that investigated the effects of stem cell therapy on left ventricular remodeling in patients after acutemyocardial infarction (AMI). Background: Intracoronary injection of stem cells in the acute phase of myocardial infarction has been proposed to replace the cardiomyocytes lost and to prevent deleterious pathological remodeling after myocardial infarction. Previously published trials have investigated the effects of cell therapy on left ventricular (LV) remodeling in AMI patients. However, the sample size of these studies is small and the conclusions are inconsistent. Methods: Trials were identified in the Cochrane Library, EMBASE, and Pub Med databases, reviews, and reference lists of relevant articles. The weighted mean difference (WMD) was calculated for net changes in LV end-diastolic and end-systolic volumes (LVEDV and LVESV) by using fixed-effect models. Results: A total of 11 trials (13 comparisons) with 832 participants evaluated the association between stem cell therapy and changes in LVEDV. Compared with the control group, stemcell therapy did not influence the LVEDV changes from baseline to follow-up (WMD: -1.76 mL, 95% confidence interval [CI]: -4.61 to 1.08 mL, P = 0.233). A total of 9 trials (11 comparisons) with 797 participants evaluated the association between stem cell therapy and changes in LVESV. Compared with the control group, patients in the cell therapy group had a significantly greater reduction in LVESV from baseline to follow-up (WMD: -5.08 mL, 95% CI: -7.80 to -2.37 mL, P < 0.001). Conclusion: This meta-analysis suggests that cell therapy improves left ventricular contractility, but has no effect on LV remodeling.