Autologous Bone Marrow Mononuclear Cell Transplantation in Ischemic Heart Failure: a Prospective, Controlled, Randomized, Double-blind Study of Cell Transplantation Combined with Coronary Bypass

Background: Bone marrow mononuclear cell (BMMC) transplantation for heart failure has shown inconsistent therapeutic efficacy.

Methods: We enrolled 104 ischemic heart failure patients scheduled for coronary artery bypass surgery (CABG). After 4- to 12-week pharmacotherapy optimization, 39 patients with left ventricular ejection fraction (LVEF) of ≤45% received injections of BMMC or vehicle intra-operatively into the myocardial infarction border area in a randomized, double-blind manner.

Results: The median number of cells injected was 8.4 × 10(8) (interquartile range [IQR]: 5.2 × 10(8) to 13.5 × 10(8)). We measured LV function and myocardial scar size by magnetic resonance imaging (MRI), and viability by positron emission tomography (PET) and single-photon emission computed tomography (SPECT), pre-operatively and after 1-year follow-up. LVEF, the pre-defined primary end-point measure, improved by a median of 5.6% in the control group (IQR 0.2 to 10.1) and by 4.8% in the BMMC group (IQR -0.5 to 8.2) (p = 0.59). Wall thickening in injected segments rose by a median of 4.5% among controls (IQR -18.1 to 23.9) and by 5.5% in the BMMC group (IQR -6.6 to 26.5) (p = 0.68). Changes in viability by PET and SPECT did not differ between groups. Myocardial scar size by MRI in injected segments rose by a median of 5.1% among controls (IQR -3.3 to 10.8), but fell by 13.1% in the BMMC group (IQR -21.4 to -6.5) (p = 0.0002).

Conclusions: BMMC therapy combined with CABG failed to improve LV systolic function, or viability, despite reducing myocardial scar size.