Increased plasma levels of fibrinogen in acute and chronic ischemic coronary syndromes.

Background: The aim of this study was to evaluate the pathophysiological role of fibrinogen in patients with chronic or acute ischemic coronary syndromes on the basis of epidemiological and clinical evidences showing the importance of fibrinogen as a risk factor for cardiovascular diseases and atherosclerosis progression.

Methods: We evaluated the behavior of plasma fibrinogen in 310 hospitalized patients with 1) acute myocardial infarction (n = 98); 2) unstable angina (n = 87); 3) chronic ischemic heart disease (n = 75); and 4) in controls without myocardial ischemia (n = 50). Fibrinogen was evaluated, by using the Clauss method, on day 1 and 5 during in hospital-stay and at 6-month follow-up in patients suffering from acute myocardial infarction.

Results: Plasma levels of fibrinogen were higher in patients with chronic ischemic heart disease (335.3 +/- 81.2 mg/dl, p < 0.001) and especially in patients with acute myocardial infarction (454.72 +/- 69.5 mg/dl, p < 0.00001) and unstable angina (382.6 +/- 101.3 mg/dl, p < 0.00025) in comparison with controls (271.28 +/- 62.4 mg/dl). Q wave myocardial infarction showed higher levels of fibrinogen than non-Q wave (461.3 +/- 95.8 vs 422.5 +/- 71.3 mg/dl, p < 0.02). Patients with acute myocardial infarction showed a further increase in fibrinogen on day 5 in comparison with entry levels (525.88 +/- 87.3 vs 454.7 +/- 69.5 mg/dl, p < 0.00001) regardless of the fibrinolytic treatment. Patients who died (n = 6) or had severe arrhythmias (n = 4) during in-hospital stay as well as those with post-infarction angina (n = 20) showed higher fibrinogen levels.

Conclusions: Our results confirm the role of fibrinogen as a risk factor for ischemic heart disease, especially in patients with unstable angina and acute myocardial infarction. In the latter, elevated fibrinogen values seem also to be associated with a worsen prognosis during hospitalization.