Cardiovascular-kidney-metabolic syndrome (CKMS) is characterized by a vicious cycle where each pathogenic link exacerbates the others, contributing to progressive deterioration in cardiac function, renal performance, and metabolic stability. The study aimed to assess kidney, heart, and metabolic functions in chronic heart failure (CHF) patients and examine these charac- teristics in dependence on endogenous intoxication severity. A number of 110 CHF patients (main group, MG) and 90 patients without CHF (control group, CG) were studied. The MG had a median age of 69.9 years, with 74.5% male patients. Echocardiographic parameters, renal function markers, and endogenous intoxication indices were measured. CKMS subgroups were stratified by estimated glomerular filtration rate (eGFR): GFR1 (>90 mL/min/1.73 m2), GFR2 (60–90 mL/min/1.73 m2), and GFR3 (<60 mL/min/1.73 m2). MG patients exhibited significantly higher serum creatinine (97.7 μmol/L versus 72.8 μmol/L) and urea levels (7.1 mmol/L vs. 5.3 mmol/L), alongside lower eGFR (67.1 vs. 87.0 mL/min/1.73 m2) compared to CG (p<0.006). Survival analysis revealed a cumulative event-free survival rate of 60.8% in patients with eGFR <60 mL/min/1.73 m2 vs. 75.2% in those with eGFR >90 mL/min/1.73 m2 (p=0.04). Structural heart abnormalities, including reduced left ventricular ejection fraction and increased left ventricle end-diastolic diameter, correlated with declining eGFR levels. Body mass index was inversely related to eGFR and positively associated with adverse cardiac remodeling, hypertension, and metabolic dysregulation. Patients with eGFR <60 mL/min/1.73 m2 demonstrated more severe lipid abnormalities and systemic inflammation, reflected in elevated fibrinogen and middle-mass molecules. CKMS in CHF patients is characterized by impaired renal filtration, metabolic instability, and cardiac dysfunction. These changes correlate with systemic inflammation and endogenous intoxication, underscoring the need for integrated therapeutic strategies targeting these interrelated pathologies.

Keywords: cardiovascular-renal-metabolic syndrome, chronic heart failure, eGFR, endogenous intoxication, systemic inflammation