Heart failure (HF) or Congestive Heart Failure (CHF) is a physiologic state in which he heart cannot pump enough blood to meet the metabolic needs of the body. Heart failure results from changes in systolic or diastolic function of the left ventricle. The heart fails when, because of intrinsic disease or structural it cannot handle a normal blood volume or, in absence of disease, cannot tolerate a sudden expansion in blood volume. Heart failure is not a disease itself, instead, the term refers to a clinical syndrome characterized by manifestations of volume overload, inadequate tissue perfusion, and poor exercise tolerance. Whatever the cause, pump failure results in hypoperfusion of tissues, followed by pulmonary and systemic venous congestion.
Because heart failure causes vascular congestion, it is often called congestive heart failure, although most cardiac specialist no longer use this term. Other terms used to denote heart failure include chronic heart failure, cardiac decompensation, cardiac insufficiency and ventricular failure.