Influence of bone marrow stem cells on left ventricle perfusion and ejection fraction in patients with acute myocardial infarction of anterior wall: randomized clinical trial: Impact of bone marrow stem cell intracoronary infusion on improvement of microcirculation.

Aims: Randomized trial to assess change in left ventricle ejection fraction (LVEF) and myocardial perfusion in patients with acute myocardial infarction (AMI) of anterior wall treated with bone marrow stem cells (BMSCs), compared with control group-from baseline in the acute phase up to 12 months of follow-up.

Methods And Results: Forty-five patients were randomized 2:1 to BMSC group (n= 31) or to control group (n = 14). Bone marrow stem cells were administered into infarct-related artery (IRA) at 4-6 day after primary PCI. Groups were followed up with Tc-99m-MIBI SPECT, radionuclide ventriculography (EF-RNV), echocardiography (ECHO), and spiroergometric stress test. Coronary angiography was repeated after 6 months. EF-RNV did not differ significantly in both groups, but trend towards increase in EF at 6 months and its maintenance after 12 months was noticed in the BMSC group. At rest study, perfusion index (PI) of region supplied with blood by IRA distal to its previous occlusion (PI-IRA) improved significantly in the BMSC group at 6 months: PI-IRA at 4-6 days vs. PI-IRA at 6 months (3.00 +/- 0.97 vs. 2.65 +/- 0.64; P = 0.017). At 12 months, PI-IRA at rest was 2.66 +/- 0.55; P = 0.07. The difference between BMSC and control groups at rest study in PI-IRA was not observed. At dipyridamole study (PI-dip), perfusion in the BMSC group was better compared with controls at 6 months (2.26 +/- 0.44 vs. 2.47 +/- 0.40; P = 0.033) and at 12 months (2.34 +/- 0.55 vs. 2.52 +/- 0.42; P = 0.014), also for region supplied with blood by IRA (PI-IRA-dip; at 6 months 2.63 +/- 0.77 vs. 3.06 +/- 0.46; P = 0.021 and at 12 months 2.71 +/- 0.63 vs. 3.15 +/- 0.51; P = 0.001). Results of LVEF, LVEDV, LVESV in ECHO and results of spiroergometric stress test did not differ significantly between groups. Major adverse cardiac events occurred more often in the control group (P = 0.027).

Conclusion: In our study, BMSC intracoronary transplantation in patients with anterior AMI did not result in increase in EF. Slight improvement of myocardial perfusion was noticed in the BMSC group. This finding may indicate better microcirculation enhanced by BMSCs, but small number of patients allow for hypothesis rather than final statement.