Randomized Controlled Trial of Moderate-Intensity Rosuvastatin With Ezetimibe Combination Therapy Versus High-Intensity Rosuvastatin on Progression of Coronary Atherosclerotic Plaque

Inclusion Criteria: * Subject must be at least 19 years of age * Subject with suspected ischemic heart disease undergoing coronary angiography and have intermediate coronary artery stenosis (30-70% by visual estimation) whose revascularization was deferred based on invasive physiologic assessment using fractional flow reserve (\>0.80) or intravascular ultrasound (minimum lumen area\> 4mm2) * Subject can verbally confirm understandings of risks, benefits and treatment alternatives of receiving statin or ezetimibe and he/she or his/her legally authorized representative provides written informed consent prior to any study related procedure. Exclusion Criteria: * Subject has calculated creatinine clearance \<30 mL/min or dialysis within 30 days. * Subject has active liver disease or persistent unexplained serum transaminase elevations (x2 x upper limit of normal \[ULN\]). * Subject requires the following concomitant medications: cyclosporine, danazol, niacin, fibrates as concomitant medications * Subject requires any of the potent CYP3A4 inhibitors, itraconazole, ketoconazole, erythromycin, clarithromycin, and telithromycin, HIV protease inhibitors, nefazodone, probucol, resins, and any investigational drugs. * Subject has an allergy/sensitivity to any statin, ezetimibe, and/or their excipients. * Subject with history of myopathy or family history of myopathy * Untreated hypothyroidism * Subject has a history of alcohol and/or drug abuse. * Subject is a pregnant or lactating woman, or woman intending to become pregnant. * Non-cardiac co-morbid conditions are present with life expectancy \<2 year or that may result in protocol non-compliance (per site investigator's medical judgment). * Unwillingness or inability to comply with the procedures described in this protocol. * Eligible patients will be randomly assigned to treatment arms, stratified by diagnosis on admission(acute coronary syndrome or stable ischemic heart disease) and presence of chronic statin use (more than one month)