The main causes of chronic heart failure (CHF) are arterial hypertension and coronary artery disease, less often cardiomyopathy, pericarditis, metastatic myocardial lesions. It should be noted that up to 50% of patients have a preserved left ventricular ejection fraction (LVEF), while its prevalence is progressively increasing annually. Acute decompensation of CHF is understood as a rapid increase in the severity of clinical manifestations (shortness of breath, severe arterial hypoxemia, the occurrence of arterial hypotension), which caused urgent medical treatment and emergency hospitalization in a patient already suffering from CHF. Decompensation of CHF requires intensification of treatment in order to stabilize the patient's condition. Strengthening diuretic therapy in addition to standard therapy helps to reduce edematous syndrome.