Coronary recanalisation rate is one of the parameters utilized to evaluate the effectiveness of a thrombolytic agent. This parameter can only be measured when the occlusion and reopening of the coronary artery involved are demonstrated by angiography. Moreover, this type of study enables the kinetics of drug activity to be accurately determined. When injected intravenously in doses of 30 units less than four hours after the onset of chest pain and when studied by this method, Eminase produces recanalisation in more than 60 per 100 of the cases. The time elapsed between injection and action is 45 minutes on average. The risk of early reocclusion is low (about 5%). The recanalisation rate obtained with Eminase is similar to that obtained with intracoronary streptokinase.