Background: inflammation is an important feature of atherosclerotic lesions and increased production of the acute-phase reactant. The contribution of coagulation factor to the development of coronary artery disease has not yet been clearly established. Objectives: To test whether C-reactive protein, fibrinogen and antithrombin-III are associated with angiographic CAD, history of myocardial infarction and extensive atherosclerotic involvement. Methods: Blood samples were tested for CRP, fibrinogen and AT-III levels from 219 individuals undergoing coronary angiography. Results: CRP was higher in patients with CAD (0.95 +/- 1.31, n = 180, vs. 0.39 +/- 0.61 mg/dl, n = 39, P < 0.0001) and in those with a history of MI (1.07 +/- 1.64, n = 96, vs. 0.65 +/- 0.72 mg/dl, n = 84, P < 0.05) than in control subjects. The patients who developed unstable angina had higher CRP levels than the patients with stable CAD (2.07 +/- 2.38, n = 7, vs. 0.80 +/- 1.13 mg/dl, n = 173, P < 0.001). Fibrinogen was significantly higher in patients with CAD than in those without CAD (298 +/- 108 vs. 258 +/- 63 mg/dl, P < 0.01). In patients with CAD. mean AT-III value was less than in patients without CAD, but this difference was not statistically significant (P = 0.08). No difference was found in CRP, fibrinogen and ATIII values among the patients with single, double or triple vessel disease. Conclusions: CRP is elevated in patients with CAD and a history of MI. Elevated levels of CRP at the time of hospital admission is a predictive value for future ischemic events. There is an association between higher levels of fibrinogen and CAD. The association of AT-III levels with CAD needs testing in further studies.