Plasma fibrinogen in unstable coronary artery disease

The fibrinogen and orosomucoid levels in plasma were studied in 249 patients within 24 h after admission to the coronary care unit because of suspected unstable coronary artery disease (CAD), i.e. unstable angina pectoris or non-Q-wave myocardial infarction (MI). Of these patients, 127 were considered to have unstable CAD either because of symptoms and signs of coronary insufficiency at a pre-discharge exercise test (n = 66) or because of the development of a probable or definite non-Q-wave MI (n = 61). The other chest pain patients without objective signs of myocardial ischaemia constituted the control group. A diagnosis of unstable CAD, and the occurrence of obesity or current smoking contributed independently to elevated fibrinogen and orosomucoid levels. In patients with non-Q-wave MI both the fibrinogen and orosomucoid levels were high regardless of obesity and smoking, indicating myocardial necrosis as a prominent cause for the elevation of these acute phase reactants. Obesity and smoking seemed to influence the metabolism of fibrinogen and orosomucoid and change their basal level and/or exaggerate their response to inflammatory stimuli. The increased fibrinogen level in unstable CAD might reflect a hypercoagulable state that contributes toward a progression of coronary lesions.