Heart 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. Heart 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.
As the heart's pumping action is lost, blood may back up in other areas of the body, producing congestion in the lungs, the liver, the gastrointestinal tract, and the arms and legs. As a result, there is a lack of oxygen and nutrition to organs, which damages them and reduces their ability to work properly.
One common cause of heart failure is coronary artery disease, a narrowing of the small blood vessels that supply blood and oxygen to the heart. Heart failure can also occur when an illness or toxin weakens the heart muscle or changes the heart muscle structure. Such events are called cardiomyopathies.
Other heart problems that may cause heart failure include heart attack, congenital heart disease, heart valve disease or arrhythmias. Diseases such as emphysema, severe anemia, hyperthyroidism or hypothyroidism may cause or contribute to heart failure.