Inability of one or both sides of the heart to pump enough blood for the body. Causes include pulmonary heart disease, hypertension, and coronary atherosclerosis. A person with left-sided heart failure experiences shortness of breath after exertion, difficulty in breathing while lying down and night breathlessness, and abnormally high pressure in the pulmonary veins. A person with right-sided failure experiences abnormally high pressure in the systemic veins, liver enlargement, and accumulation of fluid in the legs. A person with failure of both ventricles has an enlarged heart and a three-beat heartbeat. Treatment includes bed rest, medications such as digitalis, control of excess salt and water retention, and elimination of the underlying cause. See alsocongestive heart failure.