title: Intracoronary stem cell infusion after acute myocardial infarction: a meta-analysis and update on clinical trials.
abstract: BACKGROUND
  Several cell-based therapies for adjunctive treatment of acute myocardial infarction have been investigated in multiple clinical trials, but the benefits still remain controversial. This meta-analysis aims to evaluate the efficacy of bone marrow-derived mononuclear cell (BMMNC) therapy in patients with acute myocardial infarction, but also explores the effect of newer generations of stem cells.
  
  
  RESULTS
  A random-effects meta-analysis was performed on randomized controlled trials investigating the effects of stem cell therapy in patients with acute myocardial infarction that were published between January 2002 and September 2013. The defined end points were left ventricular (LV) ejection fraction, LV end-systolic and end-diastolic volumes, infarct size, and major adverse cardiac and cerebrovascular event rates. Also, several subgroup analyses were performed on BMMNC trials. Overall, combining the results of 22 randomized controlled trials (RCTs), LV ejection fraction increased by +2.10% (95% confidence interval [CI], 0.68-3.52; P=0.004) in the BMMNC group as compared with controls, evoked by a preservation of LV end-systolic volume (-4.05 mL; 95% CI, -6.91 to -1.18; P=0.006) and a reduction in infarct size (-2.69%; 95% CI, -4.83 to -0.56; P=0.01). However, there is no effect on cardiac function, volumes, or infarct size, when only RCTs (n=9) that used MRI-derived end points were analyzed. Moreover, no beneficial effect could be detected on major adverse cardiac and cerebrovascular event rates after BMMNC infusion after a median follow-up duration of 6 months.
  
  
  CONCLUSIONS
  Intracoronary infusion of BMMNC is safe, but does not enhance cardiac function on MRI-derived parameters, nor does it improve clinical outcome. New and possibly more potent stem cells are emerging in the field, but their clinical efficacy still needs to be defined in future trials.
authors.affiliation: From the Department of Cardiology, Thoraxcenter, Erasmus University Medical Center, Rotterdam, the Netherlands (R.d.J., J.H.H., S.S., E.B.); and Department of Cardiology, University Medical Center Utrecht, Utrecht, the Netherlands (H.J.D.).
authors.forename: Renate
authors.initials: R
authors.lastname: de Jong
authors.forename: Jaco H
authors.initials: JH
authors.lastname: Houtgraaf
authors.forename: Sanaz
authors.initials: S
authors.lastname: Samiei
authors.forename: Eric
authors.initials: E
authors.lastname: Boersma
authors.forename: Henricus J
authors.initials: HJ
authors.lastname: Duckers
mesh_terms: D064987:Cell- and Tissue-Based Therapy / Q000379:methods*; D005500:Follow-Up Studies; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000473:pathology; D007261:Infusions, Intra-Arterial / Q000009:adverse effects / Q000379:methods*; D008279:Magnetic Resonance Imaging; D009203:Myocardial Infarction / Q000473:pathology / Q000503:physiopathology / Q000628:therapy*; D016032:Randomized Controlled Trials as Topic; D033581:Stem Cell Transplantation / Q000009:adverse effects / Q000379:methods*; D013318:Stroke Volume / Q000502:physiology; D016896:Treatment Outcome
keywords: acute myocardial infarction; cell- and tissue-based therapy; mesenchymal stromal cells; stem cells