Accelerated Hemostasis in Coronary Artery Disease

Reduced antithrombin III levels and positive paracoagulation tests occur in some cases of coronary artery disease. This could be related to the cause of atherosclerosis or it could be the result of the disease itself. Thirty-one patients who had arteriosclerotic heart disease, well documented coronary artery occulusions (1-2 vessels), and were subjected to coronary artery bypass surgery were studied for active hemostatic mechanisms of coagulation. Plasma fibrino-peptide A (FPA) levels, fibrinogen, paracoagulation tests, and antithrombin III assays were performed. In addition, PT, PTT, TT, ECLT, and EDP were examined. The blood samples were taken 2-3 days before surgery. Ten of 31 had elevated levels of FPA, and 21 had normal FPA. Eleven patients had positive paracoagulation tests. Six of 31 showed decreased antithrombin III. Seven had an increased fibrinogen level (over 500 mg%). Four of ten patients with elevated FPA had positive tests for paracoagulation, decreased antithrombin III and increased fibrinogen. PT, PTT, TT, Platelet counts, FDP, and ECLT were normal in all patients, except three who had shortened euglobulin clot lysis time. Evidence for activated fibrinolysis was not observed except in 3 cases with shortened englobulin clot lysis time. There was no difference between elevated FPA groups and normal groups in the postoperative period. The degree or extent of coronary artery occulsion was not correlated with the level of FPA or positive paracoagulation tests. Since there were no clinical and laboratory data suggesting disseminated intravascular coagulation, the increased FPA, positive paracoagulation and the reduced level of antithrombin III strongly favor an accelerated hemostatis, probably of localized nature.