The prevalence of heart failure has rapidly increased in the last decade and morbidity and mortality for this disease are high. Several predictors have a prognostic value in heart failure such as clinical, hemodynamic, functional, biochemical and electrophysiological patterns. The male sex, the old age and the etiology are known to be important clinical parameters and the left ventricular ejection fraction, the cardiac output and size and the pulmonary capillary wedge pressure represent important hemodynamic parameters. In recent years, exercise testing has been used for prognostic purposes and exercise capacity is an important component of the risk profile in heart failure by assessing the maximum oxygen consumption and the anaerobic threshold. Plasma levels of noradrenaline, renin, aldosterone and natriuretic peptides are related to the severity and prognosis of heart failure as well as heart rate variability, ventricular late potentials and T-wave alternans with regard to mortality due to arrhythmias.