In chronic heart failure (CHF), the heart's ability to work effectively decreases - heart failure (CHF) usually develops over a long period of time and is chronic. The number of patients with chronic heart failure is increasing in developed countries. The reason for this is the aging of the population and the rapid development of medicine, which has improved the prognosis of certain heart diseases (eg coronary heart disease, valvular disease, hypertension, atrial fibrillation) and the quality of life of patients. The prevalence of heart failure in Europe is considered to be 1-2% of the population. The frequency of chronic heart failure increases with age, and this clinical syndrome already occurs in ≥ 10% of people over 70 years of age (1). There is no accurate overview of the incidence of heart failure in Estonia, but based on the above calculations, there could be about 30,000 patients with heart failure in Estonia. The long-term prognosis of patients with heart failure is poor: 50% of patients with severe heart failure die within one year (2). Patients' prognosis worsens with each repeated episode of hospitalization. Therefore, it is important to prevent the development of heart failure and, if present, hospitalizations. The main reason for repeated hospitalizations is decompensation of chronic heart failure, the most frequent cause of which is undertreatment, which may be due to both patients' poor compliance with treatment and suboptimal treatment organized by the doctor. Studies have shown that the most undertreated are patients with clinically more severe heart failure, in whom the use of evidence-based drugs has shown the greatest benefit to the clinical cost and prognosis of the syndrome (3). Based on the results of the 2018 audit of the Estonian Health Insurance Fund "Quality of treatment of patients with heart failure", diagnosis of chronic heart failure (including assessment of functional severity) and treatment in Estonia need harmonization (4). Patients with chronic heart failure are mostly diagnosed and treated by family doctors in Estonia. Therefore, it was decided to create a treatment guide that focuses on the treatment of heart failure at the primary level.