To evaluate the influence of thrombolytic therapy (TT) on the course of acute myocardial infarction (AMI), a comparative analysis of clinical and pathological findings was conducted. The latter included post mortem examination of 35 myocardial samples from patients treated with apsac in the acute phase of the infarction. The analysis indicated the predominance of cases with unfavourable coronary heart disease, severe myocardial damage and severe AMI complications in the group of the deceased patients. The following beneficial effects of TT were reported: relatively safe stromal and parenchymal myocardial components, earlier regeneration of the connective tissue. Late TT had a negative effect on MI because more hemorrhagic infarctions occurred. The combination of TT and-myocardial repair modulators is proposed.