The prevalence of heart failure in developed countries is about 1-2 % in general and in patients above 70 years over 10 %. HFpEF is the cause of heart failure from 22 to 73 %, exact data are not available. If compared with HFrEF, patients with HFpEF are older, more frequent women with hypertension and atrial fibrillation, but less myocardial infarction in their history. Heart failure is a hemodynamic disorder and the pathophysiologic basis is cardiac output, cardiac contractility, filling pressures, wall stress during systolic and diastolic function and heart rate. The neurohumoral activation is very important for the diagnosis as well as prognosis and the most sensitive seems to be brain natriuretic peptide (BNP), respectively the precursor NT-proBNP, which become a part of the new diagnostic classification and are a part of modern treatment. Key words: heart failure - hemodynamics - neurohumoral activation.