INCREASED THROMBIN LEVELS DURING THROMBOLYTIC THERAPY IN ACUTE MYOCARDIAL-INFARCTION - RELEVANCE FOR THE SUCCESS OF THERAPY

Background. It has been suggested that thrombolysis in a feedback reaction may generate pro-coagulant activities. Methods and Results. Fifty-five patients were treated with urokinase-preactivated prourokinase (n = 35) or tissue-type plasminogen activator (n = 20) for acute myocardial infarction and underwent coronary angiography at 90 minutes and at 24-36 hours into thrombolysis, and fibrinogen (Ratnoff-Menzie), D-dimer (ELISA) and thrombin-antithrombin III complex levels (ELISA) were measured. Primary patency was achieved in 39 patients (70.9%), 13 of whom (33.3%) suffered early reocclusion. Nonsignificant decreases in fibrinogen levels were observed while D-dimer levels increased +3,008 +/- 4,047-mu-g/l (p < 0.01), differences not being significant in respect to the thrombolytic agents or to the clinical course. In contrast, while thrombin-antithrombin III complex levels decreased -4.4 +/- 13.0-mu-g/l in patients with persistent patency, they increased +7.5 +/- 13.6-mu-g/l in case of nonsuccessful thrombolysis (p < 0.02) and +11.9 +/- 23.8-mu-g/l in case of early reocclusion (p < 0.001). For patients with thrombin-antithrombin III complex levels greater than 6 ng/l 120 minutes into thrombolysis, the unfavorable clinical course was predicted with 96.2% sensitivity and 93.1% specificity. Conclusion. Generation of thrombin, occurring during thrombolysis, is a major determinant for the success of therapy and thrombin-antithrombin III levels may serve as predictors for the short-term prognosis.