The aim â to evaluate the geometry of heart contraction based on speckle-tracking echocardiography data in combatants with acute myocarditis with reduced and mildly reduced left ventricular ejection fraction.Materials and methods. 53 male combatants with acute myocarditis (AM) were examined, who were divided into 2 groups: 1st group â 30 patients with a reduced ejection fraction (EF) of the left ventricle (LV) †40 %; 2nd group â 23 patients with mildly reduced LVEF 41â49 %. The diagnosis of AM was established on the basis of the recommendations for the diagnosis and treatment of myocarditis of the All-Ukrainian Association of Cardiologists of Ukraine. All patients underwent echocardiography (EchoCG) with speckle tracking (ST) and cardiac magnetic resonance (CMR) imaging with contrast.Results and discussion. Patients of the 1st group, compared to the 2nd, were characterized by more pronounced manifestations of dilatation and more significant violation of the LV contractile function, which was evidenced by a 13.6 % higher value of the LV end-diastolic volume and a 25.4 % smaller value of the LVEF. When evaluating ST echocardiographic indicators, the value of the longitudinal global systolic strain (LGSS) of the LV in the 1st group was 43.1 % lower, its velocity by 19.2 %, and the circular systolic deformation by 20.9 % in comparison with those in the 2nd group. In addition, in the 1st group, in comparison with the 2nd, the value of the indicator of systolic deformation of the left atrium (SDLA) was almost twice smaller. According to the results of CMR, in the 1st group compared to the 2nd, a larger number of segments with the presence of delayed enhancement was determined, which indicated a larger volume of fibrotic/necrotic lesions of the LV. According to the results of the correlation analysis in the 1st group, strong reverse relationships were established between the presence of delayed contrast in â„ 4 segments of the LV and LGSS (r=â0.76; p<0.01), its speed and (r=â0.71; p<0.02) and SDLA (r=â0.52; p<0.05).Conclusions. Patients with acute myocarditis with a reduced left ventricular ejection fraction compared to patients with a mildly reduced ejection fraction were characterized by a greater violation of the geometry of the contraction of the left ventricle, which was observed on the background of a larger volume of fibrotic/necrotic lesions. With the help of correlation analysis, in combatants with acute myocarditis, a relationship was established between the presence of delayed enhancement in â„ 4 segments of the left ventricle and a decrease in indicators of longitudinal systolic deformation and its speed, as well as an indicator of systolic deformation of the left atrium.