The purpose of this study is to evaluate the additional effect of probucol or concomitant administration of cilostazol and probucol on mean carotid artery intima-media thickness (mean IMT) at year 1, 2, and 3.

Hyperlipidemic patients who are currently receiving HMGCoA reductase inhibitors(Statins) will be randomized Group A(Control), Group B(Probucol only added group) or Group C(Probucol and cilostazol added group) . Randomization will be done by the minimization method, controlling for the following factors: Country(Korea vs China) and max IMT (≥2.0mm vs.<2.0mm).

Group A : HMGCoA reductase inhibitor continued

Group B : HMGCoA reductase inhibitor continued + Probucol 250 mg PO, BID

Group C : HMGCoA reductase inhibitor continued + Probucol 250 mg PO, BID +Cilostazol 100 mg PO, BID

Inclusion Criteria:

• 1) Subjects who are at least 20 y of age at the time of informed consent (male or female)
• 2) Subjects with coronary heart disease longer than 3 months.
• 3) Subjects being treated with HMGCoA reductase inhibitors(Statins)
• 4) Subjects with an max IMT equal to or greater than 1.2 mm
• 5) Subjects with an LDL-Cholesterol less than 200mg/dl
• 6) Subjects whose voluntary written informed consent is obtained for participation in this study

Exclusion Criteria:

• 1) Subjects who took probucol within 6 months before participation of the study
• 2) Subjects who took cilostazol within 3 months before participation of the study
• 3) Subjects with a history of hypersensitivity to probucol or cilostazol
• 4) Subjects with homozygous familial hyperlipidemia*
• 5) Subjects with a triglyceride ( TG) level greater than 400mg/dL at screening
• 6) Subjects with uncontrolled diabetes : HbA1c level greater than 9%
• 7) Subjects with New York Heart Association (NYHA) classification: Class Ⅲ and Ⅳ
• 8) Subjects with a QTc interval greater than 450msec(male) 470msec(female)
• 9) Subjects with serious ventricular arrythmias (frequent episodes of multifocal ventricular extrasystole)
• 10) Subjects with atrial fibrillation (including paroxysmal AF)
• 11) Subjects with unstable angina
• 12) Subjects with liver and kidney functions that satisfy the following criteria - AST or ALT >100 IU/L, serum creatinine >1.5 mg/dL
• 13) Subjects who are participating in another clinical trial
• 14) Subjects with pregnant or possibly pregnant without appropriate contraception control. Appropriate contraception control means that Oral contraception for greater than 4 weeks, surgical contraception including loop insertion, condom use etc. Women who has no possibility of pregnancy because of surgery or menopause should not be regarded the subject with possibly pregnant
• 15) Subjects with clinically significant disorders of blood coagulation
• 16) Subjects who are not considered by the physicians to be appropriate to participate in this trial for any other reason