Acute phase proteins in patients with acute coronary syndrome: correlations with diagnosis, clinical features and angiographic findings

Background: C-reactive protein (CRP) plasma levels increase in patients with acute coronary syndrome (ACS). The role and implications of increased plasma concentrations of other acute phase proteins (APPs), such as alpha-1-antitrypsin (A1AT), alpha-1 glycoprotein (A1GP), haptoglobin (HG), ceruloplasmin (CP), and C3c and C4 complement fraction, in patients with ACS are still not completely defined. Methods: A total of 218 consecutive patients with ACS were included in the study, 185 with acute myocardial infarction (AMI) and 33 with unstable angina (UA). In all patients, A1AT, A1GP, HG, CP, C3c and C4 complement fraction, and CRP were evaluated within 12 h after the onset of symptoms. Sixty-two patients with AMI underwent coronary angiography. Results: APPs showed a significant correlation with CRP concentrations. Patients with AMI had higher concentrations of A1AT and HG than UA patients. Cholesterol levels were correlated with APPs in patients with AMI. Patients with three coronary vessel disease or LAD disease had significantly higher C3c concentrations. Coronary collateral flow was associated with higher A1GP and CP concentrations, and total coronary occlusion with A1AT and CP. Conclusions: APPs were correlated with CRP concentrations in subjects with ACS. The increase in APPs in patients with ACS seems to be linked to the entity of myocardial damage and coronary atherosclerotic burden.