The present study is intended to assess the vulnerability of plaques seen on CCTA by means of TVC Imaging System and to make comparisons between plaques with adverse plaque characteristics and ones without adverse plaque characteristics in terms of plaque volume and lipid core contents.

This study is to be conducted in two phases - Phases 1 and 2. In Phase 1, the vulnerability of plaques seen on CCTA will be assessed with TVC Imaging System, and the plaque volume and lipid core contents of plaques with versus without adverse plaque characteristics will be compared. For the purpose of this study, the study of this phase will be a cross-sectional study in which the shapes of vulnerable plaques seen on CCTA will be compared to their vulnerability visualized by the TVC Imaging System.

In Phase 2, the patients with multi-vessel (polyvascular) disease of those participating in Phase 1 will be included, and the study of this phase will be a longitudinal study in which serial TVC imaging will be performed for non-target vessels, and any differences in changes of plaque vulnerability when treated with moderate-dose versus high-dose statin will be comparatively analyzed. The purpose of the present study is to determine whether there are any significant differences in changes of plaque volume and stability when treated with high-dose versus moderate-dose statin.

Inclusion Criteria:

1. Age 20 years of older
2. Patients with typical chest pain or evidences of myocardial ischemia (e.g., stable, unstable angina, silent ischemia and positive functional study or reversible changes in the electrocardiogram (ECG) consistent with ischemia
3. Patients with signed informed consent
4. Confirmed coronary artery disease in computed tomography

Exclusion Criteria:

1. The past history of coronary artery disease (e.g., myocardial infarction, percutaneous coronary intervention (PCI), coronary artery bypass graft surgery (CABG), etc.)
2. Less than 2-year life expectancy due to non-cardiac disease
3. If the subject cannot voluntarily agree in writing to participate in this study
4. If the subject is currently participating in any other study with another investigational drug or medical device
5. Allergic reaction to iodinated contrast media
6. Significant renal dysfunction (Serum creatinine > 1.5 mg/dl) 7 Heart rate ≥ 80 beats per minute even after treatment with a heart rate lowering medication which disable to take CCTA

8. Contraindications of either β blockers or nitroglycerin 9. The past history of complex congenital heart disease 10. Pregnant women or women with potential childbearing 11. Body mass index (BMI) exceeding 35 12. Irregular heartbeats which disable to take CCTA 13. Contraindications of statin due to hypersensitivity, past history of serious complication such as myopathy or increased liver enzyme more than 3 times of normal upper limit