This course aims to provide a specialized overview on the use of biomarkers in the diagnosis and prognosis of heart failure (HF). The use of biomarkers is now essential for a correct diagnosis of heart failure, to establish a forecast of prognosis and also to guide the choice of the best possible therapy. This course analyzes the biochemical bases and cutoff levels for the main biological markers used in clinical practice in the setting of patients with heart failure or suspected heart failure based on the clinical picture.