Aim. To determine the peculiarities of heart failure (HF) development in human immunodeficiency virus (HIV)-infected patients, depending on the blood concentration of C-reactive protein (CRP).Material and methods. This cross-sectional screening clinical trial included 100 patients hospitalized with HIV infection and a history of HF for 28 months. The patients were divided into 2 groups depending on blood CRP concentration. The cut-off point was CRP of 15 mg/l. The first group included 37 HIV-infected patients with HF and blood CRP <15 mg/l, while the second group — 63 HIV-infected patients with HF and CRP concentration ≥15 mg/l. The inclusion criteria were HIV infection and prior HF, stable medical state, taking into account the underlying disease that required hospitalization. The study did not include patients with acute cardiovascular diseases within prior 3 months, acute decompensated and acute heart failure, cancer, infectious diseases, conditions that required surgical intervention. N-terminal pro-brain natriuretic peptide (NT-proBNP) was determined in all patients.Results. Correlation analysis revealed a strong inverse relationship between the blood concentrations of NT-proBNP and CRP (r=-0,639; p<0,005). A ROC curve revealed the most optimal cut-off threshold of 9,8 mg/l (AUC=0,796, p<0,05), which ensures sensitivity of 92,9% (p<0,05) and specificity of 57,6% (p<0,05). The odds ratio (OR) of an increase in NT-proBNP >450 pg/ml, and hence the risk of acute decompensated HF in the presence of a CRP concentration of 1-9,8 mg/l in HIV-infected patients with HF was 44,73 (95% CI=8,62;311,10), while relative risk (RR) — 18,73 (95% CI=4,94;112,94). In the presence of in hospital inflammatory diseases and CRP ≥15 mg/l in HIV-infected patients and prior HF, the RR of acute decompensated HF is reduced by 88% (RR=0,12, 95% CI=0,03-0,33).Conclusion. CRP values from 1 to 9,8 mg/l in HIV-infected patients with HF are predictors of its severity, characterized by a higher incidence of HF with reduced ejection fraction, diastolic dysfunction and left ventricular hypertrophy without significant differences with patients who have CRP >9,8 mg/l. CRP concentration >9,8 mg/l in HIV-infected patients and prior HF indicates the development of an inflammatory process, and not a worsening of the HF course.