Two-dimensional and doppler echocardiography were used in examination of 90 patients with noncoronary myocardial diseases (myocarditis, cardiosclerosis after myocarditis, dilated cardiomyopathy) and NYHA class I-IV heart failure. Complex approach was applied to the study of severity of myocardial dysfunction, its relation to intracardiac, systemic and pulmonary hemodynamics, and detection of levels of compensatory reactions of the myocardium and reserve mechanisms of the cardiovascular system. Echocardiography during exercise on bicycle in patients with myocarditis and postmyocarditis cardiosclerosis with class I-II heart failure allowed to establish the following early signs of myocardial damage and concealed heart failure: doppler index of global contractility exceeding 0,5 (p<0,01) and isovolumic contraction time longer than 0,05 sec (p<0,01). There was a significant correlation between complex of selected diagnostically important hemodynamic parameters (cardiac output, pulmonary artery pressure, total peripheral resistance, index of global contractility, dp/dt, E/A) and severity of class II-IV heart failure in noncoronary myocardial diseases.