Abstract
ADP-induced platelet aggregation and levels of fibrinogen, alpha2-macroglobulin, alpha1 antitrypsin, antithrombin III and plasminogen were measured in 12 patients after 1 to over 30 days from the attack of myocardial infarction. The patients had the past history of cerebral thrombosis, diabetes mellitus with arteriosclerotic complications or persistent hypertension for 5 years and they were defined as arteriosclerotic group in past history. Other 12 patients with acute myocardial infarction and without the above arteriosclerotic past history (non-arteriosclerotic group) and 12 healthy people were also examined. Three groups showed similar distributions in their age and sex. The arteriosclerotic group showed an enhancement of platelet aggregation and a low level of immunological antithrombin III in comparison with those in the non-arteriosclerotic patients immediately after the infarction. Both the abnormalities in the arteriosclerotic group were observed over 30 days after the attack of infarction, while the changes in the non-arteriosclerotic group returned rapidly to normal ranges. Although changes in plasma fibrinogen, alpha2-macroglobulin and plasminogen are related to the climical Course of myocardial infarction, a significant difference was not observed between both the groups after infarction. The results would suggest that main causes of abnormal platelet aggregation and antithrombin III after the attack of myocardial infarction might be depended on the presence of an overt arteriosclerosis in their past history.
