Contrary to its name, heart failure does not mean the heart has failed completely. It means the heart is pumping inefficiently and no longer can meet the body's need for blood. This inefficient pumping causes a backup of blood in the veins leading to the heart, and causes the kidney to retain fluid. As a result, the body's tissues swell. The swelling (edema) most commonly affects the legs, but it also can occur in the lungs, causing breathing difficulty, and in other tissues and organs.
Heart failure often is the end stage of another form of heart disease. Its many causes include:
Coronary artery disease
High blood pressure (hypertension)
Heart valve disorders (including rheumatic heart disease)
Congenital heart disorders
Cardiomyopathy (disease of the heart muscle)
Cardiac arrhythmias (problems with the heart rate and/or rhythm)
Exposure to toxins, including excessive alcohol
Hyperthyroidism, diabetes and chronic (long-lasting) lung disease also increase the risk of heart failure.
In some people with heart failure, the heart muscles become weaker and cannot pump as well. In other people, the heart muscles become stiff and the heart cannot fill with enough blood between heartbeats.
The number of cases of heart failure continues to increase in the United States. This probably is the result of an aging population, together with medical advances that have prolonged the lives of people with other forms of heart disease, allowing heart failure to develop.