Structural and functional parameters of myocardium were evaluated with 2D+ Doppler echocardiography in two similar age groups of MS patients: S1: 12 subjects in 3-4 Degrees EDSS (Expanded Disability Status Scale), S2: 12 subjects in 5-7 degrees EDSS. The control group comprised 12 healthy subjects temporarily (at least 1 month) immobilized due to lower limb fractures. Investigations were performed in the supine position and 3 min after tilting to the erect position. Symptoms of organic myocardial injury which might have caused its insufficiency were not observed in any subjects. All structural parameters evaluated by this method did not differ significantly in the examined groups. Symptoms suggesting myocardial insufficiency were found in patients from group S2. Statistically significant decrease of ejection fraction (EF) and cardiac output (CO) was observed in the supine position of S2 patients as compared to S1 and the controls. These symptoms intensified in the erect position in S2 patients and they were accompanied by the decreased values of stroke volume (SV). The fact that in the majority of patients orthostatic hypotonia was not observed and that those disorders were not compensated by significant intensification of heart rate suggest to us that besides disorders resulting from autonomic nervous system dysfunction they may have been caused by secondary myocardial injury in the course of MS.