Value of blood coagulation tests in ischemic cerebral disease

80 patients with transitory ischemic attacks (TIA) and 30 patients with cerebral infarction (CI) were investigated regarding hemostatic disturbances to evaluate selected coagulation test methods for routine laboratory use. The patients were studied a few days after the first appearance of symptoms and at defined times subsequently. The study included measurements of circulating platelet aggregates; platelet adhesiveness, factor-VIII-related antigen (VIIIR:Ag), fibrinolytic activity after venous stasis, alpha-2-antiplasmin activity, and antithrombin III activity. Platelet aggregates and/or adhesiveness were increased in the acute stage in most patients as well as in patients with recurrent attacks. Increased platelet adhesiveness was also found in some patients with nonvascular neurologic diseases. Factor VIIIR:Ag was increased especially in the acute stage and more in patients with recurrent attacks. Diminished fibrinolytic response after venous stasis was found in about 40% of the TIA and in 50% of the CI patients as well as in all patients who died from vascular disease. Antiplasmin activity was increased especially in women. Antithrombin activity was increased during warfarin treatment. The effect of acetylsalicylic acid (ASA) treatment on platelet function was registered only in women but ASA seemed to influence mechanisms other than platelet function, e.g. normalization of factor VIIIR:Ag. Our findings indicate that with methods available for the routine laboratory the measurement of fibrinolytic response to venous stasis, factor VIIIR:Ag and platelet reactivity would be of value in selecting risk patients and following the effect of treatment.