The lack of consensus concerning the diagnostic criteria of cardiac failure explains the relative paucity of epidermiological data. Most of the available information comes from American health registers and the Framingham study: in the United States, there are more than 3 million people with cardiac failure (over 1% of the population) and over 400,000 new patients each year. Cardiac failure is the main cause of death in 40,000 deaths and an associated cause in a further 250,000 deaths. In the Framingham study (1948-1988) the mean survival time after diagnosis is 1.7 year in men and 3.2 years in women, corresponding to 1 and 5 year survival rates of 57% and 25% in men and 64% and 38% in women. These figures are worse than those of the large scale therapeutic trials of the last 10 years and represent survival of the most severe cases. Although not strictly epidemiological data, analysis of the large scale trials allows evaluation of the clinical features and survival of patients under optimal medical treatment (ACE inhibitors associated with other treatments): these results are important to bear in mind when considering alternative therapies (transplantation, mechanical assist devices), the accessibility of which may be limited for reasons of availability or cost. In terms of public health, it is important that accurate epidemiological data concerning cardiac failure. In particular severe cardiac failure, is made available in France.