The aim of this study was non-invasive assessment of cardiac function in patients with systemic lupus erythematosus (SLE). In a group of 36 patients with SLE transthoracic echocardiography, standard ECG and the 24-hour ECG Holter monitoring were performed and the results were compared to a control group of 35 healthy volunteers. Significantly lower mean values of heart rate variability (HRV), the presence of late ventricular potentials and tendency to tachycardia were detected in SLE patients when compared to the control group. On echocardiography examination valvular lesions were found in 15 SLE patients but only in 5 of them were insignificant mitral or aortic regurgitant jets observed. Echocardiography did not reveal abnormalities in cardiac dimensions and left ventricle systolic function. Abnormal indexes of left ventricular filling were found in 3 patients. All SLE patients with antiphospholipid antibodies had some cardiovascular manifestation.