The Application of the Umbilical Cord Mesenchymal Stem Cells in the Complex Treatment of Non-ischemic Heart Failure

Inclusion Criteria: * Men and women aged 18 years and older * Registered at the Research-Clinical Center for Cardiac Surgery and Transplantology * Established diagnosis of non-ischemic dilated cardiomyopathy (NYHA Class III-IV) * Non-ischemic etiology confirmed by coronary angiography or contrast-enhanced cardiac CT * Left ventricular ejection fraction (LVEF) ≤ 35% based on echocardiography or cardiac CT * Clinical indications for implantation of an implantable cardioverter-defibrillator (ICD), regardless of actual implantation status * No clinical or laboratory signs of dysfunction or insufficiency of other major organs * No history of malignancy within the past 5 years and no abnormal tumor markers * Signed written informed consent Exclusion Criteria: * Ischemic heart disease or prior cardiac surgery, including coronary artery stenting * Significant valvular heart disease, intracardiac thrombus, left ventricular aneurysm, hypertrophic, postpartum, alcoholic or restrictive cardiomyopathy, congenital heart defects, or resistant hypertension * Stroke within the past 2 years * Autoimmune or immunodeficiency disorders * Polyvalent allergy * Decompensated chronic comorbidities * Use of systemic corticosteroids, cytotoxic or immunosuppressive drugs (e.g., cyclophosphamide, methotrexate, cyclosporine, azathioprine) within 4 weeks before enrollment * Positive tests for hepatitis B or C, syphilis, or HIV/AIDS * Active systemic infections requiring targeted antibiotic therapy * Unt…