Long-term myocardial functional improvement after autologous bone marrow mononuclear cells transplantation in patients with ST-segment elevation myocardial infarction: 4 years follow-up‡

To evaluate the safety profile and efficacy of bone marrow mononuclear cells (BMMNC) transplantation for ST-segment elevation myocardial infarction (STEMI) by assessing patients and their left ventricular function at up to 4 years follow-up. Eighty-six patients with STEMI who had successfully undergone percutaneous coronary intervention (PCI) were randomized to receive intracoronary injection of BMMNC (n = 41) or saline (n = 45). Left ventricular ejection fraction, as evaluated by UCG, was markedly improved at 6 months (0.484 +/- 0.5 vs. 0.457 +/- 0.6, P = 0.001), 1 year (0.482 +/- 0.7 vs. 0.446 +/- 0.6, P < 0.001), and 4 years (0.505 +/- 0.8 vs. 0.464 +/- 0.8, P < 0.001) after BMMNC transplant when compared with control group. However, the current cell therapy did not improve the myocardial viability of the infarcted area as assessed by single-photon emission computed tomography analysis at 4 years post-transplant (0.263 +/- 0.007 in BMMNC group vs. 0.281 +/- 0.008 in control group, P = 0.10). During the follow-up period, one control group case (2.2%) of in-stent restenosis was confirmed by coronary angiography and underwent repeat PCI. Also during follow-up, one death (2.2%) occurred in the control group, and one patient (2.4%) in the BMMNC group had transient acute heart failure. This study indicates that intracoronary delivery of autologous BMMNC is safe and feasible for STEMI patients who have undergone PCI, and can lead to long-term improvement in myocardial function.