The investigators sought to assess whether plasma myeloperoxidase (MPO) levels differ among patients with stable and unstable CAD patients and control subjects, and correlate with inflammatory and clinical risk factors such as ox-LDL, NO,leptin, adiponectin, sPLA2, Lp-PLA2, homocysteine and 3-nitrotyrosine in the patients.

Elevation of the leukocyte enzyme myeloperoxidase (MPO) in stable coronary artery disease (CAD) patients in contrast to unstable CAD patients is controversial and its relationship with some inflammatory and noninflammatory markers such as oxidized LDL (ox-LDL) and nitric oxide (NO) in the CAD patients has not been evaluated yet. Evaluation of these relationships is the aim of the study.Also the relationships between MPO and some other inflammatory biomarker such as leptin, adiponectin, sPLA2, Lp-PLA2, homocysteine and 3-nitrotyrosine are examined. This study includes 50 stable CAD, 50 unstable CAD patients and 50 controls. Plasma MPO, ox-LDL, leptin, adiponectin, sPLA2 levels are determined using enzyme immunoassay.Homocysteine and 3-nitrotyrosine are measured using HPLC-fluorescence method. Plasma total NO and other risk factors such as lipid profile, hypertension, smoking, diabetes mellitus and familial history of CAD are also determined in the patients. Results are statistically analysed and the association between all markers are assessed.

Inclusion Criteria:

• Stable and unstable patients with angiographically documented coronary artery disease.
• Control subjects without angiographically documented coronary artery disease.

All subjects Exclusion Criteria:

• Patients with recent (with in 6 month) myocardial infarction or cardiovascular events,
• surgery (with in 3 month),
• cancer and
• infective or inflammatory diseases were not included in the study.

All subjects are diagnosed angiographically following chest pain, clinical manifestations or suspected changes on ECG at Isfahan Cardiovascular Research Center in Iran