Effect of pioglitazone on endothelial dysfunction after sirolimus-eluting stent implantation

Previous studies have demonstrated endothelial dysfunction after sirolimus-eluting stent (SES) implantation. The present study evaluated the effect of pioglitazone on endothelial dysfunction after SES implantation in nondiabetic patients. A total of 50 nondiabetic patients who had undergone SES implantation were randomly assigned to the pioglitazone group (n = 25) or the control group (n = 25). Endothelial function was estimated by measuring the coronary vasoreactivity in the reference segment within 15 mm proximal and distal to the SES in response to intracoronary acetylcholine infusion (10(-8) and 10(-7) mol/L) at 9 months of follow-up. Endothelium-independent vasomotion was assessed after an intracoronary bolus of nitroglycerin. Changes in the coronary diameter in response to 10(-8) and 10(-7) mol/L acetylcholine in the segment proximal to the SES were not significantly different between the pioglitazone and control groups. In contrast, in the segment distal to the SES, vasoconstrictions to 10(-8) (-3.0 ± 2.8% vs -7.1 ± 4.5%, p <0.01) and 10(-7) mol/L acetylcholine (-6.2 ± 8.0% vs -13.1 ± 8.9%, p <0.01) were attenuated in the pioglitazone group compared to the control group. Endothelium-independent vasodilation to nitrate did not differ between the 2 groups. Multivariate analysis showed that pioglitazone was an independent predictor improving endothelial dysfunction after SES implantation. In conclusion, pioglitazone might improve endothelial dysfunction after SES implantation in nondiabetic patients.