FFR Versus IVUS With Angiography-Derived FFR for Clinical Outcomes in Patients With Coronary Artery Disease

Inclusion Criteria: * Subject must be ≥ 19 years. * Subject is able to verbally confirm understanding of risks, benefits and treatment alternatives of receiving invasive physiologic or imaging evaluation and PCI with a drug-eluting stent (DES) and he/she or his/her legally authorized representative provides written informed consent. * Subjects suspected with ischemic heart disease. * Subjects with coronary artery diameter stenosis 50-90% by angiography-based visual estimation eligible for stent implantation. * Target vessel size ≥ 2.5mm in visual estimation. Exclusion Criteria: * Known hypersensitivity or contraindication to any of the following medications: Heparin, Aspirin, Clopidogrel, Prasugrel, Ticagrelor * Active pathologic bleeding. * Gastrointestinal or genitourinary major bleeding within the prior 3 months. * History of bleeding diathesis, known coagulopathy. * Non-cardiac co-morbid conditions with life expectancy \< 2 years. * Target lesion located in coronary arterial bypass graft. * Left main coronary artery stenosis ≥ 50%. * Chronic total occlusion in the study target vessel. * Culprit lesion of ST-elevation myocardial infarction (STEMI). * Not eligible for angiography-derived FFR (ostial RCA ≥ 50% stenosis, severe tortuosity, severe overlap, poor image quality).