Aims: We sought to determine whether repeat administration of bone marrow mononuclear cells (BMC) can improve left ventricular function compared with a single infusion in patients with large acute myocardial infarction (AMI).
Methods and results: Thirty-nine patients with a ST-elevation AMI of the anterior wall and a significantly decreased left ventricular ejection fraction (LVEF 20-39%) were randomly assigned to three groups following primary percutaneous coronary intervention: Group A (n = 12) received a single intracoronary infusion of BMC (1.9 +/- 1.2 x 10(8)) at 3-7 days after AMI; Group B (n = 15) received BMC administration both at 3-7 days (2.0 +/- 1.4 x 10(8)) and at 3 months (2.1 +/- 1.7 x 10(8)); and the control group (CON, n = 12) received one placebo injection at 3-7 days. We noted no severe complications associated with the BMC transfer. The increase in LVEF evaluated by magnetic resonance imaging (MRI) after 12 months in Group B (11.7 +/- 2.6%) was significantly greater than that in Group A (7.2 +/- 1.6%, P < 0.001) or in CON (2.9 +/- 2.0%, P < 0.001). Magnetic resonance imaging-derived myocardial infarct size decreased significantly in Group B compared with Group A (11.3 +/- 2.7% vs. 6.3 +/- 1.6%, P < 0.001).
Conclusion: Data from this preliminary study suggest that repeated BMC administration might be a safe and feasible therapeutic strategy for patients with large AMI.