Echographic evaluation of systolic function plays an important role in examination of the patients with acute myocardial infarction (AMI). Recent developments in real-time 3D echocardiography (RT3DE) allow us to evaluate additional parameters such as the dyssynchrony.The aim of this study was to evaluate the relationship between myocardium dyssynchrony and systolic function and to assess the prognostic value of dyssynchrony and its influence on the development of arrhythmias and fatal event in post AMI period.Methods: Study population consisted of 82 (mean age 52±21) patients with AMI and 65 age and gender matched persons with similar cardiovascular risk factors, but without AMI (control group). Standard deviation of the time to the regional LV minimum systolic volume for all 16 segments Tmsv4 16-SD index was used for the assessment of dyssynchrony. The follow-up period was 6 months afterAMI.Results: Tmsv 16-SD values were significantly higher in patients with MI compared control group (6.8 ± 2.7% vs 2.9 ± 1.6 % respectively, р<0,001). Moderate negative correlation was observed between Tmsv 16-SD and Cardiac Index (CI) (r =-0.58, p<0.008). No significant correlations were found between Tmsv 16-SD and mean arterial pressure and herat rate. Tmsv 16-SD was significantly lower in patients with pulmonary hypertension (maximum systolic pressure in lung artery (SPLA) – 55.0±5.58 mm Hg) as compared to patients without pulmonary hypertension (maximum SPLA – 33.0±5.76 mmHg); 4.9±0.75 vs 6.1±1.88 respectively, р=0.03. Significant positive correlation was observed between Tmsv 16-SD and end-diastolic volume (EDV) (r=0.63; р<0.05) and negative with ejection fraction (EF) (r=-0.73; p<0.05).28 patients (34%) of the MI group had the increase Tmsv 16-SD and normal values of EDV and EF. According to ROC analysis ROC Tmsv 16-SD>6.1 was associated with arrhythmic complications in post IM period (sensitivity 83.3%, specificity 87.5%, AUC=0.865, p<0.0001). Tmsv 16SD>6.1 correlates with increasing likelihood of fatal event (sensitivity 87.5%, specificity 71.6%, AUC=0.81, p<0.0001)Conclusions: Tmsv 16-SD is increased in patients with MI. In 34% of MI patients the increase of Tmsv 16-SD was observed in combination normal values of EF and EDV which allow us to consider Tmsv 16-SD as an additional indicator describing pathological changes in myocardium. Tmsv16-SD is correlated with hemodynamic indicators such as CI and SPLA. High Tmsv 16-SD is associated with increased level of arrhythmic complications and fatal events.