Plasma fibrinogen levels and the clinical course of acute myocardial infarction.

Plasma fibrinogen levels were followed from admission to the coronary care unit up to 3 months after an acute myocardial infarction (AMI) (51 patients at entry--49 patients at follow-up). Mean initial value as determined with 24 hours of onset of symptoms was 522 mg% +/- 205 S.D. Peak value 845 mg% +/- 215 S.D. was reached 3-5 days after onset of symptoms. Mean fibrinogen level on a later follow-up was similar to the initial value (521 mg% +/- 145 S.D.). Our data confirm that a rise in the plasma fibrinogen level is common after myocardial necrosis. No correlation was found between the maximum peak value and the clinical course of the disease. However, death, reinfarction and cardiogenic shock were more frequent among patients with an initial plasma fibrinogen level higher than 400 mg%. Our findings suggest that the acute increase in fibrinogen following necrosis is less significant to the clinical course than a chronically high plasma fibrinogen level.