ABSTRACT
This study was conducted on 20 patients with acute myocardial infarction [AMI] and 20 healthy persons, as a control group, they were clinically free from any systemic disease. It was found that the mean TAT level was highly significantly increased in patients with AMI when compared to healthy persons and can be used as an additional criteria for diagnosis of AMI. There was a positive correlation between the mean level of TAT and the extent of infarction. After administration of thrombolytic therapy there was another elevation in the mean TAT level which may indicate reperfusion of the infarct area. Also, after administration of heparin, here was another elevation which may be due to the fact that heparin accelerate the reaction between thrombin and antithrombin III