DefinitionHeart failure, also called congestive heart failure, is a condition in which the heart can no longer pump enough blood to the rest of the body.Alternative NamesCHF; Congestive heart failure; Left-sided heart failure; Right-sided heart failureCauses, incidence, and risk factorsHeart failure is almost always a chronic, long-term condition, although it can sometimes develop suddenly.The condition may affect the right side, the left side, or both sides of the heart.Right-sided heart failure means the right ventricle of the heart loses its pumping function.Left-sided heart failure means the heart's ability to pump blood forward from the left side of the heart is decreased. The left side of the heart normally receives blood rich in oxygen from the lungs and pumps it to the remainder of