Animal studies have suggested that bone marrow cell injection can improve myocardial perfusion and improve ventricular function in chronic ischaemia, but the two randomized trials performed to date in humans have yielded conflicting results.

To investigate the effect of intramyocardial bone marrow cell injection on myocardial perfusion and left ventricular (LV) function further, Ramshorst et al. randomised 50 patients with chronic myocardial ischaemia to either intramyocardial injection of autologous bone marrow cells or placebo solution (25 patients per group). The primary outcome measure was myocardial perfusion as assessed by the summed stress score, a 17-segment score for stress myocardial perfusion assessed by Tc-99m tetrofosmin single-photon emission computed tomography (SPECT), while secondary measures included LV ejection fraction (LVEF) as assessed by MRI, Canadian Cardiovascular Society (CCS) angina class, and the Seattle Angina Questionnaire quality-of-life score.

After 3-months of follow-up, the summed stress score improved from 23.5 (SD, 4.7) to 20.1 (SD, 4.6; p<0.001) in the bone marrow cell group, compared with a decrease from 24.8 (SD, 5.5) to 23.7 (SD, 5.4; p=.004) in the placebo group. In those patients who underwent MRI, a 3% increase in LVEF was seen in the bone-marrow cell treated patients at 3 months (95% CI, 0.5% to 4.7%), but the placebo group showed no improvement. Improvements in CCS class an quality-of-life score were significantly greater in bone marrow cell-treated patients that in placebo-treated patients (p=.03 and p=.04, respectively).

Conclusion:

In this small study of patients with angina refractory to medical treatment, intramyocardial bone marrow injection resulted in a statistically significant improvement in myocardial perfusion, ejection fraction, and quality-of-life at 3 months. Whether this translates into an improvement in morbidity and mortality outcomes requires verification in further long-term studies.

· Van Ramshorst J, Bax JJ, Beeres SLMA et al. Intramyocardial bone marrow cell injection for chronic myocardial ischemia: a randomized controlled trial. JAMA (2009) vol. 301 (19) pp. 1997-2004