The Gut Microbiome in Chronic Heart Failure

Inclusion Criteria: * Age over 18 years * Residing in the city of Astana and surrounding regions (Akmola region) * Diagnosis of heart failure according to internationally recognized guidelines and classified as Class I-IV by NYHA (New York Heart Association) or Stage A-C according to ACC/AHA (American College of Cardiology/American Heart Association) classification * Clinically stable condition and optimized medication therapy for heart failure for at least 4 weeks in accordance with current recommendations * Willingness to participate in the study Exclusion Criteria: * • Age under 18 years * Refusal to undergo diagnostic procedures specified in the study protocol * Terminal stage of heart failure (Stage D according to ACC/AHA classification) * Coronary or peripheral revascularization procedures, valvular procedures, or any major surgical procedure within 3 months prior to study enrollment * Use of antibiotics, cytostatic therapy, or pro- or prebiotics within 1 month prior to the baseline visit * Presence of oncological and autoimmune diseases (connective tissue diseases, gastrointestinal disorders, skin disorders, etc.) * Acute illness or active infection * Individual intolerance to the administered nutrients (probiotics) * Presence of other anatomical or comorbid conditions, or other medical, social, or psychological conditions that, in the investigator's opinion, may limit the subject's ability to participate in the clinical study, comply with the requirements of subsequent follow-up, or affect the scientific validity of the clinical study results.