[Significance of the thrombin-antithrombin III complex in the diagnosis of pulmonary embolism and deep venous thrombosis--comparison with fibrinopeptide A, platelet factor 4 and beta-thromboglobulin].

In 22 patients with suspected pulmonary embolism and 19 patients with suspected deep vein thrombosis, thrombin-antithrombin III complex (TAT) as an indicator of thrombin activation was measured using a newly developed ELISA. For comparison fibrinopeptide A (FPA), as a marker of an activated coagulation, as well as platelet factor 4 (PF4), and beta-thromboglobulin (beta-TG), as markers of platelet activation, were determined. In all patients in whom pulmonary embolism was confirmed by perfusion lung scan and in 15 of 16 patients in whom deep vein thrombosis was confirmed by phlebography, TAT exceeded the upper limit of normal (3.0 ng/ml). FPA was increased in 71% of the pulmonary embolism patients, PF4 in 53%, and beta-TG in 59%. The data for the patients with deep vein thrombosis were comparable. PF4 and beta-TG were increased in more than 25% of the normal controls, FPA in 17%, and TAT in 9%. TAT is very sensitive in detecting an activation of the coagulation system in patients with suspected thromboembolic events. The test, however, is not specific for thromboembolism; it only indicates an activation of the coagulation system. Acute pulmonary embolism or deep vein thrombosis would appear to be unlikely if TAT is normal. The measurement of TAT is easier and less susceptible to disturbances than that of FPA, PF4, and beta-TG.