Abstract 4402: Endothelial Progenitor Cell Capture in Stented Porcine Coronary Arteries Increases Endothelialization but Does Not Affect Intimal Thickening
Introduction. The introduction of drug eluting stents (DES) has reduced the need for target lesion revascularization, but their effects on healing, inflammation and vascular dysfunction has emphasized the need to design strategies that improve current DES. One such strategy is to improve endothelialization (EC) by capturing CD34-positive endothelial progenitor cells (EPC) by the stent surface, an approach supposed to improve healing and reduce neointimal thickening (NIT). The first clinical trial using coronary EPC capture stents showed stent safety, but (though underpowered) NIT was not reduced as compared to bare metal stents (BMS). So far, no clinical study has shown efficacy. We therefore studied the coronary response to EPC capture between 48 hours and 90 days.
Hypothesis. EPC capture increases endothelialization without affecting NIT.
Methods The stent, coated with a murine anti-human monoclonal CD34 antibody, was assessed in normal coronary arteries of swine for
% EC at 2, 5 and 7 days and
NIT at 28 and 90 days in comparison to BMS (n=12 per stent).
Results. EPC capture showed a higher % EC than BMS at 2 days, reaching statistical significance at 5 days (p<0.05). Morphometry of NIT at 28 and 90 days showed no significant differences for EPC (339±56 and 169±49μm) and BMS (210±18 and 185±31μm) when corrected for parameters of vascular injury (0.7±0.1 and 0.1±0.04).
Conclusions. EPC capture stents increase early endothelialization, but do not affect intimal thickness as compared to BMS at 28 and 90 days. We propose that only strategies that improve endothelial function may be more effective. Thus, EPC capture may increase safety but not efficacy.