Objective We used serial intravascular ultrasound(IVUS) to analyze stent edges of drug-eluting stents(DES). Method We used the POET trial data which is a prospective, multicenter, randomized trial for evaluating the efficacy of adjuvant balloons in procedure using DESs randomly allocated (SES vs. PES). Serial(baseline and 8month follow-up) IVUS analysis was performed at 5mm reference segments proximal and distal to the DES. Results A total 301 patients with denovo lesion were treated and baseline characteristics showed no significant differences between groups. At the proximal edge, SES showed significant constrictive vascular remodeling(65.10짹20.08mm2 to 61.65짹18.71mm2, p=0.041), whereas PES showed significant plaque progression(22.77짹12.34mm2 to 26.81짹11.68mm2, p=0.006). All these resulted in significant lumen area decrease in both group(40.27짹10.23mm2 to 36.51짹10.17mm2 in SES & 37.57짹11.10mm2 to 31.74짹10.57mm2 in PES, p<0.05 in both/ p=ns when comparing SES & PES). At the distal edge, only SES showed significant change in plaque area(12.58짹9.20mm2 to 14.33짹10.06mm2, p=0.02), which did not resulted in lumen area decrease(29.90짹10.29mm2 to 28.70짹9.19mm2, p=ns) because of mild positive vascular remodeling(42.39짹18.16mm2 to 43.03짹17.82mm2). There were no significant area changes in PES. Conclusion After stenting using DES, IVUS revealed significant luminal dicrease only at proximal edge caused by some negative remodeling(more pronounced in SES) and plaque progression(more pronounced in PES).