Efficacy and Safety of Intracoronary Autologous Bone Marrow‐Derived Cell Transplantation in Patients With Acute Myocardial Infarction: Insights From Randomized Controlled Trials With 12 or More Months Follow‐Up

BACKGROUND: Until now there was no systematic review concerning the chronic effects of intracoronary bone marrow-derived cell (BMC) transplantation in patients with acute myocardial infarction (MI). HYPOTHESIS: Improvement of cardiac function in patients with acute MI post BMC transplantation might last longer than 12 months. METHODS: We searched MEDLINE, EMBASE, and the Cochrane database through June 2009. Eligible studies were randomized controlled trials of intracoronary BMC transfer in acute MI patients with follow-up duration equal to or longer than 12 months. RESULTS: A total of 8 trials involving 725 participants were identified. Compared with controls, BMC transplantation significantly improved left ventricular ejection fraction (LVEF) by 4.37% (95% confidence interval [CI]: 2.66%-6.08%; P < 0.00001), reduced left ventricular end-diastolic volume (LVEDV) by 5.71 mL (95% CI: 2.03-9.40 mL; P = 0.002), left ventricular end-systolic volume (LVESV) by 8.94 mL (95% CI: 4.22-13.66 mL; P = 0.0002), and infarct size by 2.42% (95% CI: 1.33%-3.51%, P < 0.00001). Bone marrow-derived cell treatment also significantly reduced the risk of death (relative risk [RR]: 0.33, 95% CI: 0.13-0.89; P = 0.03), while the risk of reinfarction was similar between the 2 groups (RR: 0.62, 95% CI: 0.09-4.12; P = 0.62). Subgroup analysis showed that the BMC transplantation-induced LVEF increase was more significant in patients age < 55 and with cells transferred 6 or 7 days after MI. CONCLUSION: Beneficial effects of intracoronary BMC transplantation could last more than 12 months in acute MI patients.