assessment in patients with Type 2 diabetes mellitus in addition to cOronary artery disease after Percutaneous coronary intervention with regard to Sitagliptin-induced COronary plaque REgression (TOP-SCORE)

INTERVENTION: Interventions (sitagliptin group) The period of intervention: 8‐12 months The dosage of Sitagliptin: 50‐100mg/day Control (non‐sitagliptin group) CONDITION: Coronary artery disease with type 2 diabetes mellitus (T2DM) PRIMARY OUTCOME: Nominal change in percent atheroma volume (PAV) from baseline to 8‐12 month`s follow‐up determined by IVUS after Sitagliptin treatment IVUS SECONDARY OUTCOME: (1) Percent change in total atheroma volume (TAV) determined by IVUS ; (2) Change in levels of low‐density lipoprotein cholesterol, triglyceride, high‐density lipoprotein cholesterol, hemoglobin A1c, blood sugar and blood pressure ; (3) Association between lipid profile and the change in PAV; (4) Association between biomarker and the change in PAV INCLUSION CRITERIA: (1) T2DM patients 30 years of age or older who needed percutaneous coronary intervention (PCI) (2) T2DM patients with a baseline hemoglobin A1c (National Glycohemoglobin Standardization Program) level of 6.2% to 9.9% (if taking any hypoglycemic agents) or 6.5% to 9.9% (if receiving no medical treatment) (3) Patients treated dyslipidemia according to Japan Atherosclerosis Society Guideline for the Diagnosis and Prevention of Atherosclerotic Cardiovascular Diseases 2007 or 2012 version (4) written consent for participation in the study