Timing of granulocyte-colony stimulating factor treatment after acute myocardial infarction and recovery of left ventricular function: Results from the STEMMI trial

BackgroundGranulocyte-colony stimulating factor (G-CSF) therapy after ST-elevation myocardial infarction (STEMI) have not demonstrated impact on systolic recovery compared to placebo. However, recent studies suggest that timing of G-CSF therapy is crucial.MethodsTiming of G-CSF treatment was analyzed in the STEMMI MRI subpopulation including 54 patients with STEMI treated with primary percutaneous coronary intervention (PCI) < 12 h after symptom onset. Patients were randomized to double blind treatment with G-CSF (10 µg/kg/day) or placebo. Treatment was initiated from 17 to 65 h (mean 30) after PCI. Left ventricular ejection fraction (LVEF) was evaluated with MRI.ResultsRecovery of LVEF from baseline to 6 months was not associated with time from PCI to G-CSF. An identical improvement in LVEF was found in the placebo group and the G-CSF group (p = 0.8). There was no correlation between time from PCI to G-CSF and maximum plasma concentration of CD34+ cells (r = − 0.3, p = 0.1).Similar results were found from data on recovery of the infarction size and change in the systolic wall thickening.ConclusionsIn the time window from 17 to 65 h after STEMI treated with PCI, the timing of G-CSF treatment does not seem to affect the recovery of LVEF. It remains to be determined if very early, or very late G-CSF treatment might be effective.