Heart failure (HF) is a disorder in the structure or function of the heart that prevents it from maintaining adequate oxygen supply to other tissue. It manifests with symptoms and signs of damage to almost all target organs. The most common cause is damage of the systolic function of the left ventricle, but causes include disrupted diastolic function, valvular diseases, pericardial and endocardial diseases, and heart rhythm disorders. The diagnosis of HF can be established using both invasive and non-invasive techniques. The goal of HF treatment is to reduce the symptoms and signs of the disease, reduce rehospitalization, and improve the quality and length of the patient's life. Three neurohormonal antagonists play a key role in the treatment: angiotensin-converting enzyme inhibitors (or angiotensin receptor blockers), beta-blockers, and mineralocorticoid receptor antagonists. Refractory HF in the terminal phase can be treated with heart transplants and cardiac support pumps, which can be uni- or biventricular and either temporary or permanent. [ABSTRACT FROM AUTHOR]