Stem cells mobilization in acute myocardial infarction (stem-AMI trial): preliminary data of a perspective, randomized, single blind trial.

AIM

Clinical trials demonstrated that granulocyte colony-stimulating factor (G-CSF) administration seems to be safe in patients with acute myocardial infarction but the results about the effectiveness are not so encouraging. The main problem is to distinguish the effects that early revascularization and regenerative therapy have on left ventricular (LV) function. The purpose of our perspective randomized trial is to evaluate the efficacy of G-CSF administration, assessed by improvement of LV ejection fraction by cardiac magnetic resonance imaging (MRI), in patients with acute anterior myocardial infarction undergoing primary percutaneous coronary intervention (PCI) and with evidence of LV dysfunction.

METHODS

Fifty consecutive patients with first anterior ST-elevation myocardial infarction (STEMI), undergoing primary PCI, with symptom to balloon >2 and <12 hours and ejection fraction (EF) =or<45%, are randomized to 150 microg/m2 G-CSF bis in die subcutaneously (from day 0 to day 4) in addition to standard care. Patients are submitted to echocardiography, Holter monitoring, gated single photon emission computed tomography (SPECT) and MRI at baseline and at 6 months of follow up. Coronary angiogram is repeated at 6 months to evaluate in-stent restenosis.

RESULTS

From July 2006 until August 2007, 13 consecutive patients were enrolled and 5 of them were assigned to G-CSF administration. All patients underwent PCI and stenting of left anterior descending artery. Mean baseline EF evaluated by echocardiography, SPECT and MRI was respectively 36%, 33% and 38%. No adverse events were observed during G-CSF administration. The mean white blood cells count, in the treatment arm, was 36.1 x 10(9)/L +/- 2.90 on day 5.

CONCLUSION

Preliminary data of our study do not support any conclusive result. However, the characteristics of our population could allow us to distinguish the effects that revascularization and regenerative therapy have on LV function in patients with acute myocardial infarction.