THE EFFICACY AND RELATIVE FIBRIN SELECTIVITY OF PROUROKINASE IN PATIENTS WITH ACUTE MYOCARDIAL INFARCTION

Abstract

The use of thrombolytic agents in acute myocardial infarction has gained widespread acceptance as an important early therapeutic option. Acute coronary thrombosis has been found in approximately 80% of patients with acute infarction and the use of standard thrombolytic agents opens these occluded vessels in most cases. Unfortunately, in many individuals standard agents also produce a systemic lytic state with its attendant hemorrhagic complications. Prourokinase (PUK) has been shown to be a relatively fibrin selective thrombolytic agent in vitro owing to its localized conversion to urokinase at the clot surface. Because of this desirable property, we studied the efficacy and selectivity of PUK in vivo in 19 patients with acute myocardial infarction. Each of these patients was documented by angiography to have a totally occluded infarct-related artery. Each patient was treated within six hours (range: 2 to 5.8 hours) of the onset of symptoms with 62.5 mg of PUK derived from the human kidney cell line, TCL598, infused intravenously over 90 minutes. Complete vessel patency was achieved in nine patients within 61 ± 19 minutes of the start of the infusion without apparent hemorrhagic complications. We evaluated the effect of PUK on fibrinogen, on nonspecific fibrinogen degradation products (FDP) the the fibrinogen/fibrin I peptide, Bβ 1-42, as well as on the specific fibrin degradation products, D-dimer (XDP) and the fibrin II peptide, Bβ 15-42. Values for these parameters measured before and at the end of the 90-minute infusion of PUK are given as the mean ± S.E.M.We conclude that PUK is an effective agent with which to achieve coronary thrombolysis and that at the doses used in this study, it aDDears to be relatively fibrin selective.