Heart failure is defined as the inability of the heart to deliver a cardiac output sufficient for the needs of the periphery. The mechanisms responsible for ventricular failure always correspond for changes in ventricular filling that may have 2 origins: decrease in ventricular systolic function, leading the ventricle to operate on the vertical part of its pressure volume relationship; primary decrease in ventricular distensibility. An increase neurohormonal stimulation participates in sodium retention and in the preservation of blood pressure. The mechanisms leading to the progressive alteration of the haemodynamic status are not perfectly known, but a progressive increase in wall stress and myocyte loss are likely to occur.