Changes in serum lipoprotein(a) and C4b-binding protein levels after acute myocardial infarction.

We investigated changes in serum lipoprotein(a) (Lp(a)) and C4b-binding protein (C4bp) levels following acute myocardial infarction (AMI). Serum lipids, apolipoproteins, C-reactive protein (CRP), sialic acid and haptoglobin (Hp) were also measured and evaluated. The study involved 16 patients (11 men, 5 women, mean age 68.2 +/- 8.4 years) with AMI admitted within 12 h after the onset of illness. CRP rose sharply and immediately after the onset of AMI, reaching its maximum level on the 3rd day of illness. This was followed by temporary increases in sialic acid and Hp, both of which peaked on the 7th day of illness. The Apo A-I level was significantly lower on the 14th day, while the Apo B level was significantly lower on the 3rd day. Serum total cholesterol (T-Ch), HDL-Ch and LDL-Ch showed temporary decreases after the onset of illness. Serial examination of the serum of patients with AMI yielded the following findings; 1) Both Lp(a) and C4bp levels rose temporarily with similar patterns of variation, and 2) they took longer time to peak (around the 14th day) and lasted longer than the increases in the other acute reactive proteins.