Late vascular response at the edges of sirolimus analogous-eluting stents in diabetic patients

ABSTRACT

Introduction: Vascular response at edges of drug-eluting stents is still not well established, particularly in diabetic patients who are prone to aggressive atherosclerosis progression. Recently, Biolimus and Zotarolimus have demonstrated potent antiproliferative deffects. Objective: To compare the vascular responses at edges of sirolimus analogous-eluting stents in patients with and without diabetes, using intravascular ultrasound (IVUS). Methods: 306 edges were analyzed in 153 patients treated with drug-eluting stents and divided in diabetics (122 edges) and nondiabetics (166 edges). IVUS was performed postintervention and at 6-month follow-up and included 5 mm distal and proximal to the stented segment. Vessel, lumen, and plaque volumes were calculated. Volume variation (follow-up minus basal) was also calculated. Edge restenosis was defined as obstruction 50%. Results: Baseline characteristics were similar between groups. In both groups the entire lesion length was covered (stent length/ lesion length ratio was 1.5 for both groups). There were no differences in edge volumes and restenosis rate between the groups. Among diabetics, there was no significant volume variation. However, in nondiabetic patients there was significant increase in vessel volume in proximal (from 67.1 6 22 mm3 to 72.2 6 25 mm3 P = 0.02) and distal (from 54.4 6 22 mm3 to 59.8 6 22 mm3 P = 0.001) edges. Conclusion: Nondiabetic patients showed a significant positive vascular remodeling in proximal and distal edges of sirolimus analogous-eluting stent. This vascular mechanism was not observed in diabetic patients. Although different vascular responses were observed, restenosis rates were equivalent between the 2 groups at 6-month follow-up.