The highly dosed short-term therapy of thrombolysis with intravenous streptokinase at the beginning of therapy less than or equal to 6 angina pectoris time has with a high probability as a consequence the early recanalisation of a coronary thrombosis. A reduction of the lethality is significant, however, furthermore also patients with longer angina pectoris time have advantages. The combination of the intravenous streptokinase therapy with the immediate medication of acetyl salicylic acid (ASA) is a decisive factor for the decrease of the reocclusion and the reinfarction rate, respectively, and thus for the limitation of the lethality. The early intracoronary streptokinase therapy is no more indicated today. In comparison to the intravenous streptokinase the early recanalisation rate is higher in t-PA and APSAC. However, at present the results are identical at dismission from hospital. Studies in the nineties must make evident the advantages of the various substances only in the direct comparison (Sk, t-PA, APSAC).