Abstract 13575: Stem Cell Mobilization by Granulocyte-Colony Stimulating Factor Does not Increase Neointimal Volume or Non-Culprit Coronary Plaques After Sirolimus-Eluting Stent Implantation
Introduction: Stem cell mobilization by granulocyte-colony stimulating factor (G-CSF) attenuates the endothelial dysfunction in mechanically disrupted artery models. However, some clinical studies have shown increased neointimal hyperplasia in patients who underwent bare metal stent implantation. Furthermore, the effect of stem cell mobilization on non-culprit plaques is unknown.
Hypothesis: We evaluated whether the degree of stem cell mobilization by G-CSF correlates with neointimal volume or change in non-culprit coronary plaques after sirolimus-eluting stent (SES) implantation.
Methods: This double-blinded randomized placebo-control study (primarily designed to evaluate the effect of stem cell mobilization by G-CSF on endothelial function after SES implantation) assigned patients to the G-CSF group (n=50) or the placebo group (n=50). After successful SES implantation, the patients received subcutaneous injection of G-CSF (300 μg daily) or saline for 5 days. CD34+ cells were quantified at baseline and at post-treatment (day 5). Follow-up angiography and intravascular ultrasound (IVUS) were performed 9 months after SES implantation. The percentage of neointimal volume to stent volume (%NIV) at follow up and percent change in plaque volume (ΔPV) of non-culprit segments (which were defined as more than 5 mm proximal or distal from the stent) between post-procedure and follow-up were measured by IVUS. Correlations between post-treatment CD34+ level and %NIV and ΔPV at proximal and distal segments were investigated using Pearson’s correlation coefficient test.
Results: Plasma CD34+ cell level significantly increased after G-CSF injection (0.94 ± 0.55 vs. 18.39 ± 13.55/μL, p <0.001) but did not in the placebo group (0.93 ± 0.68/μL vs. 1.35 ± 2.36/μL, p = 0.22). Follow-up IVUS was available in 39 (78%) G-CSF and 43 (86%) placebo patients (p = 0.30). There were no significant correlations between post-treatment CD34+ level and %NIV (r = -0.102, p = 0.370), ΔPV at proximal (r = 0.111, p = 0.446) and distal (r = -0.023, p = 0.872) non-culprit segments.
Conclusion: The degree of stem cell mobilization by G-CSF does not correlate with neointimal volume and changes in plaque volume at non-culprit coronary segments after SES implantation.
- © 2013 by American Heart Association, Inc.