What is congestive heart failure?

(CNN) - For years Hollywood icon Elizabeth Taylor had struggled with congestive heart failure, a chronic condition in which the weakened heart cannot pump enough blood throughout the body.

Taylor, 79, died Wednesday at Cedars-Sinai Hospital in Los Angeles after six weeks of hospitalization, her publicist said.

Congestive heart failure occurs when the heart can no longer keep pace with circulation needs. The blood backs up in veins and other parts of the body such as the liver, lungs and lower extremities. The condition also affects the kidneys' filtering ability. Patients commonly see swelling in their legs and ankles. They can also have trouble exerting themselves, easily experiencing shortness of breath and fatigue, according to the American Heart Association.

Conditions that tax the heart, such as narrowed arteries (coronary artery disease), past heart attacks, high blood pressure, heart valve disease, infections or congenital defects can cause heart failure.

Most people with mild and moderate conditions can be treated with medication and lifestyle changes, like more exercise, less salt in the diet, less stress and weight management. More drastic cases may require valve replacement or even a heart transplant. Taylor once had heart valve replacement surgery.

About 2.5 million women in the United States are affected by the condition, according to the Cleveland Clinic.