Atherosclerosis is a progressive disease. Lipid lowering therapy was the standard treatment for patients with coronary artery disease. Studies indicated that coronary artery plaque progression had positive relationship with the plasma cholesterol level, and could be halted or reversed by intensive statin therapy (such as 20-40 mg/d atorvastatin). Ezetimibe plus statin could further lowered blood cholesterol level. Here the investigators hypothesize that same cholesterol lowering level by routing dose of atorvastatin or lower dose of atorvastatin plus ezetimibe could achieve the same effect on coronary artery plaque cessation or regression.

Inclusion Criteria:

• Willing to receive the coronary angiography and potential PCI therapy

Exclusion Criteria:

• Patients was treated by statins before randomization
• Patient with ≤ 20% and ≥ 70% coronary narrowing and target lesion
• ST elevation myocardial infarction less than 7 days
• Without informed consent
• Abnormal liver function before randomization, (AST, ALT ≥ULN)
• Active hepatitis or muscular disease
• Impaired renal function with serum creatinine level > 3mg/dl
• Impaired left ventricular function with LVEF > 30%
• Participate in other studies