Clinical Comparison of Low-dose Rosuvastatin Plus Ezetimibe Combination Therapy and High-dose Rosuvastatin Monotherapy in Patients With Minimal to Intermediate Coronary Artery Disease Without Percutaneous Coronary Intervention

Inclusion Criteria: 1. Male and female adjusts (19 or older) 2. Patients with suspected stable angina pectoris without coronary artery interventions, who showed a minimal to intermediate coronary artery diseases (a stenosis of 10 to 70% diameter as per QCA) in at least one natural coronary artery in coronary artery angiography or coronary artery CT. 3. Patients who gave their informed consent themselves in writing. 4. Patients who were treated with statin or lipid-lowering agents may participate in the study by changing the existing medicines. Exclusion Criteria: 1. Patients with an intermediate (\>30%) lesion on the left main coronary artery. 2. Patients diagnosed with acute coronary artery diseases (STEMI, NSTEMI, Unstable angina) 3. Patients who received percutaneous coronary intervention 4. Patients who have been diagnosed with stroke, transitory ischemic attack, and peripheral artery diseases. 5. Patients diagnosed with variant myocardial infarction 6. Patients with severe liver diseases or lung diseases and/or malignant tumor with life expectancy of less than 3 years 7. Patients with severe valvular heart disease 8. Patients who are hypersensitive or prohibited from using the active substance (Ezetimibe or Rosuvastatin) of the study medicines 9. Patients with cardiogenic shock 10. Pregnant women or women who are planning to get pregnant 11. Patients who are receiving hemodialysis or peritoneal dialysis or received renal transplantation due to end-stage renal failure 12. Patients who participated in other clinical studies within the past three months (except for non-interventional observation studies)