Many forgotten methods of treatment, known since ancient times, are increasingly reviving in the current conditions of the development of medicine and pharmacy, once again proving the validity of their existence. One of them is hirudotherapy (from Latin hirudina - leech) or bdelotherapy. Treatment with leeches has begun since ancient times. Probably, even prehistoric people accidentally noticed a positive effect after a leech bite. Hebrew Persian, Hebrew and Ancient Indian texts that mention the benefits of leeches contain references to the benefits of leeches. Hirudotherapy was considered one of the aspects of this medical technique, since bleeding has been the most popular method of treating many diseases for thousands of years. Self-treatment with leeches in those days was not yet carried out, since healers believed that leeches were needed only to remove excess blood. It was considered more convenient to use them instead of knives, because the procedure was completely painless. Materials and methods 100 patients with chronic heart failure of II-III functional class according to NYHA classification aged 55 to 77 years, 80 men and 20 women, were examined. Of these, 71 patients were diagnosed with chronic heart failure of functional class II, 29 - chronic heart failure of FC III. The cause was the development of chronic heart failure: postinfarction cardiosclerosis (78 patients) and small-focal cardiosclerosis (22 patients). Results The effect of hirudotherapy on the clinical course of the disease in patients with chronic heart failure with normal blood pressure in 42 patients with coronary heart disease was studied. By the end of hirudotherapy, an improvement in the clinical condition was noted in 33 patients (78.5%), which resulted in a decrease in the functional class of chronic heart failure according to the results of the six-minute walk test. Chronic heart failure I FC was diagnosed in 12 patients with initially verified chronic heart failure II FC before discontinuation of the course of treatment, followed by a tendency to increase the distance of a six-minute walk. Conclusions Hirudotherapy has a positive effect on hemostasis in patients with chronic heart failure, which is expressed in the normalization of the concentration of fibrinogen and soluble fibrin-monomer complexes, an increase in the content of plasminogen in the blood, a decrease in spontaneous and ADP-induced platelet aggregation.