Aim. To compare effect of percutaneous balloon angioplasty (PCA) and a systemic thrombolysis (STL) on the central and intracardiac hemodynamics in patients with acute coronary syndrome (ACS) with ST segment elevation.Material and methods. 80 patients with ACS with ST segment elevation were included in the study. Patients were split into 2 groups depending on reperfusion strategy. PCA was performed in 55 patients (first group). 25 patients of the second group had STL with Streptokinase, i/v, 1 500 000 units per hour. Echocardiography was performed in all patients at admission and after 3 and 7 days of treatment to evaluate intracardiac hemodynamics.Results. Both reperfusion methods significantly increase of ejection fraction (EF) and maximal output speed of left ventricle (LV). Increase of LV EF in patients after PCA was higher than this in patients after STL. PCA improved LV diastolic function; STL did not change this characteristic. After PCA working diagnosis of ACS was transformed to the following final diagnosis: acute myocardial infarction (AMI) with Q, AMI without Q and unstable angina in 37,5, 30,4 and 32,1% of patients, respectively. After STL diagnosis of AMI with Q was defined in all patients.Conclusion. PCA in patients with ACS with ST segment elevation results in fast improvement of global systolic and diastolic LV function. Besides, PCA prevents AMI with Q in a half of these patients.