Various microRNAs such as miRNA-21, -126, -143, -145 are involved in the restenosis and atherosclerosis progression (Figure 1). Changes in these miRNAs from baseline to 9 months after randomization have never been studied, and the effects of pioglitazone in correlation with the changes in various miRNAs could be utilized in clinical practices. Comparison of pioglitazone and placebo on 9 months follow-up neointima volume and neointima characteristics by optical coherence tomography (OCT) will be conducted.