Heart failure refers to a dysfunction as a result of which the heart can no longer meet the needs of the body, causing reduced blood flow and accumulation (congestion) of blood in the veins and lungs and/or other changes that can further weaken or stiffen the heart.
Heart failure can occur in individuals of any age, even in young children (especially those with congenital heart disease). However, it is much more common among the elderly, as this population is more prone to diseases that predispose to heart failure (such as coronary artery disease, which damages the heart muscle) or heart valve disease. Age-related cardiac changes can also make the heart less efficient.