Fractional Flow Reserve (FFR) Versus Intravascular Ultrasound (IVUS) in Intermediate Coronary Artery Disease

Inclusion Criteria: Clinical indication: * Patients with angina or patients with documented silent ischemia * Patients who are eligible for intracoronary stenting * Age \> 18 years old, \< 75 years old Angiographic indication: * Intermediate coronary artery disease (30-70% diameter stenosis) by visual estimation * Reference vessel diameter ≥ 3.0mm by visual estimation Exclusion Criteria: * Acute or old myocardial infarction * Previous coronary artery bypass graft * Left main disease (≥ 50% stenosis) * In-stent restenosis lesion * Chronic total occlusion * Low ejection fraction (\< 40 %) * Graft vessel lesion * History of bleeding diathesis or coagulopathy * Limited life-expectancy (less than 1 year) due to combined serious disease * Contra-indication to heparin, everolimus * Contraindication to aspirin, clopidogrel or cilostazol * Pregnant