Soluble fibrin complexes in coronary disease

Abstract

The occurrence of intravascular coagulation in coronary artery disease was evaluated by measurement of soluble fibrin complexes (SFC). Using 4% agarose and a long column it was possible to quantify by gel filtration the SFC including high molecular weight fibrinogen derivatives and to separate them from fibrinogen, and fibrinogen degradation products. Of 21 patients with chest pain undergoing coronary angiography, 16 patients with one or more coronary arteries significantly occluded on angiogram showed a marked increase in percent SFC (23.3 ± 3.5 SEM) while 5 individuals with chest pain and normal angiograms had only 10.9 ± 2.0% SFC. In contrast, 6 normal individuals had only 4.6 ± 1.3% of their fibrinogen in the form of SFC. A modest correlation was demonstrated between levels of SFC and degree of coronary occlusion which probably reflects the generalized atherosclerosis in these patients. Serum fibrinogen degradation products (FDP) in the patients' sera as assayed by staphlococcal clumping test were found to be moderately elevated only in patients with abnormal angiograms. The role of the intrinsic coagulation pathway was evaluated by assays of prekallikrein (preK), kallikrein inhibitors (KI) and determinations of inactive Hageman factor (factor XII). No significant changes were found in the two groups of patients when compared to normal suggesting that activation of the intrinsic pathway was not involved.