OBJECTIVETo compare the effects of intracoronary infusion of mononuclear stem cells (MNCs) or mesenchymal stem cells (MSCs) in patients with dilated cardiomyopathy (DCM).

METHODSDCM patients with left ventricular ejection fraction(LVEF) < 40% were randomized to intracoronary infusion of MNCs [(5.1 ± 2.0) × 10(8), n = 16] or MSCs [(4.9 ± 1.7) × 10(8), n = 17] or equal volume normal saline (n = 20) through the guiding catheter. Changes of left ventricular end-diastolic diameter (LVEDd), LVEF and myocardium perfusion defects were assessed before and at (30 ± 3) days and (90 ± 7) days after the procedure. Malignant cardiovascular events were also recorded.

RESULTS(1) One month after the procedure, LVEF in transplantation groups significantly increased compared to before procedure (all P < 0.05), and significant increase of LVEF was observed only in MSCs transplantation group compared to control group (P < 0.05). However, absolute changes of LVEDd and perfusion defects of myocardium were similar among and within groups (P > 0.05). (2) Comparing with before procedure and control group, LVEF in transplantation groups increased significantly in three months after the procedure (P < 0.05), but there were no significant differences between transplantation groups (P > 0.05). LVEDd and myocardium perfusion defects in transplantation groups improved significantly compared with that of before procedure (P < 0.05), while significant decrease of myocardium perfusion defects was only observed in patients treated with MSCs compared with control group at three months after procedure (P < 0.05). (3) There were no significant differences in major cardiovascular events between transplantation group and control during follow-up (P > 0.05).

CONCLUSIONSIntracoronary bone marrow stem cells transplantation is safe and effective for DCM patients while the efficacy of MSCs and MNCs transplantation is comparable.