The purpose:to follow-up the pathological changes in the cardiac muscle using contrast-enhanced MRI (in comparison with endomyocardial biopsy), in patients with chronic heart failure due to dilated cardiomyopathy.Materials and methods.This study comprised 29 pa tients (as 51.1 ± 11.03 years old). Everybody underwent cardiac contrast- enhanced MRI, at admission and in 6 month, the endomyocardial biopsy was carried out in 19 patients.Results.Myocarditis with different degrees of activity was revealed in 14 patients, from the results of a histological examination of the cardiac muscle. The patients were assembled to two groups, depending on the severity of the inflammatory changes; the data were compared with the results of the endomyocardial biopsy. In the group of patients with a moderate degree of activity of the inflammatory process, myocardial fibrosis prevailed, in the group of patients with pronounced activity it was oedema, with a relatively smaller volume of myocardial fibrosis. In six months of monitoring, the number of pathologically altered segments of the myocardium increased (from 2.7 ± 1.7 to 3.05 ± 1.7) and the thickness of the paramagnetic contrast uptake to the cardiac muscle also increased (from 4.4 ± 1.4 to 4.8 ± 1.9 mm), despite the specific therapy kept carried out this time. Conclusion.The development of dilated cardiomyopathy and chronic heart failure, in a significant number of cases causes of inflammatory changes in the myocardium, followed by manifestation of dilated cardiomyopathy, and the progression of fibrotic changes in the myocardium was observed even after elimination of the causative agent.