Cardiovascular disease (CVD) is the leading cause of Taiwan. American Heart Association (AHA) indicated that CVD patients with Statin therapy would decrease the recurrence of CVD. The goal for lipid lowering in CVD patients was set at the level of low-density lipoprotein cholesterol (LDL-C) below 100 mg/dL. Coenzyme Q10 is recognized as a lipid soluble antioxidant, Statin treatment might affect the level of coenzyme Q10. Therefore, the purposes of this study are going to investigate the relation of coenzyme Q10 with other antioxidant vitamins (Vitamin A and E), the markers of lipid peroxidation, antioxidant enzymes activities, and the inflammatory markers in coronary artery disease (CAD) patients during Statin therapy. The study is going to design a placebo-controlled study. The investigators will recruit coronary artery disease (CAD) patients who are identified by cardiac catheterization as having at least 50% stenosis of one major coronary artery, and healthy subjects. CAD subjects are randomly assign to placebo and coenzyme Q10 supplements (150 mg/bid = 300 mg/d) groups. Intervention is going to administration for three months. Fasting blood will be obtained in each month and determine the concentration of antioxidant vitamins, lipid peroxidation markers, antioxidant enzymes activities after intervention. Meanwhile, the investigators will measure the level of inflammatory markers in all subjects of this study. Hopefully, the results of this study could provide information of coenzyme Q10 supplementation for clinical dietitian in advising CAD patients who are under Statin therapy.

Inclusion Criteria:

CAD patients is identified by cardiac catheterization as having at least 50% stenosis of one major coronary artery and under statin therapy.

Exclusion Criteria:

• age < 18 years old
• pregnancy women
• taking antioxidant vitamins supplements