Survival of Fibrinogen Degradation Products in the Circulation after Thrombolytic Therapy for Acute Myocardial Infarction

Abstract The total amount of fibrinogen and fibrin degradation products (TDP) and, separately, those derived from fibrinogen (FDP) were measured in plasma with enzyme immunoassays (ETA) using monoclonal antibodies. Blood was collected from five patients before and at regular intervals after thrombolytic therapy of acute myocardial infarction (AMI) with streptokinase (SK). After 500 000 U SK i.v. and approximately 250 000 U SK i.c. administered within 2 h, the level of TDP rose to a mean of 338 μg/ml (± S.D.: 208–547) and declined monoexponentially with a half-disappearance time of ∼5h. FDP reached a peak value of 214 (127–362) μg/ml and disappeared with the same speed as TDP. It was shown that the disappearance curves were not influenced by persistent fibrinolytic activity of the blood, which disappeared immediately after the completion of the SK infusion with an apparent half-life of 64 min. Collection of blood in citrate with aprotinin, instead of citrate only, did not result in lower TDP or FDP levels. Due to its speed and reliability, the assay of TDP or FDP with the new ETA, soon after thrombolytic therapy in AMI, may predict the optimal time for surgical intervention or for starting anticoagulant treatment in order to prevent rethrombosis.