Clinical usefulness of a functional test of neutralising streptokinase antibodies for the prediction of the thrombolytic effect of streptokinase in acute myocardial infarction.

We investigated whether the occurrence of neutralising streptokinase (SK) antibodies, as assessed by a new bedside test, was related to the effect of SK in acute myocardial infarction (AMI), assessed with continuous vectorcardiography (VCG). Twenty-eight patients with ST elevation, admitted </= 6 h after the onset of symptoms, treated with 1.5 MIU SK were included. The level of SK antibodies was assessed by the TAS Streptokinase Test Panel, measuring the lysis time of clotted fibrin in the sample. Clot lysis time was negatively correlated to ST vector magnitude (ST-VM) recovery at 90 min (r(S) = -0.40, p = 0.03), and clot lysis time was positively correlated to time to reperfusion, (r(S) = 0.42, p = 0.03). The predictive values of the test, however, were low. In conclusion, as the prediction of reperfusion in AMI after SK by the new test was poor, we cannot recommend it for clinical decision-making prior to the choice of the thrombolytic agent.