WebMD Medical Reference in collaboration with

Heart Disease: Your Guide to Heart Failure

Heart failure affects nearly 5 million Americans. Roughly 550,000 people are diagnosed with heart failure each year. It is the leading cause of hospitalization in people older than 65.

Heart failure does not mean the heart has stopped working. Rather, it means that the heart's pumping power is weaker than normal. With heart failure, blood moves through the heart and body at a slower rate, and pressure in the heart increases. As a result, the heart cannot pump enough oxygen and nutrients to meet the body's needs. The chambers of the heart respond by stretching to hold more blood to pump through the body or by becoming more stiff and thickened. This helps to keep the blood moving for a short while, but in time, the heart muscle walls weaken and are unable to pump as strongly. As a result, the kidneys often respond by causing the body to retain fluid (water) and sodium. If fluid builds up in the arms, legs, ankles, feet, lungs or other organs, the body becomes congested, and congestive heart failure is the term used to describe the condition.

Heart failure is caused by many conditions that damage the heart muscle, including:

• Coronary artery disease. Coronary artery disease (CAD), a disease of the arteries that supply blood and oxygen to the heart, causes decreased blood flow to the heart muscle. If the arteries become blocked or severely narrowed, the heart becomes starved for oxygen and nutrients.
  
  
• Heart attack. A heart attack may occur when a coronary artery becomes suddenly blocked, stopping the flow of blood to the heart muscle and damaging it. All or part of the heart muscle becomes cut off from its supply of oxygen. A heart attack can damage the heart muscle, resulting in a scarred area that does not function properly.
  
  
• Cardiomyopathy. Damage to the heart muscle from causes other than artery or blood flow problems, such as from infections or alcohol or drug abuse.
  
  
• Conditions that overwork the heart. Conditions including high blood pressure (hypertension), valve disease, thyroid disease, kidney disease, diabetes or heart defects present at birth can all cause heart failure. In addition, heart failure can occur when several diseases or conditions are present at once.

© 2005-2013 WebMD, LLC. All rights reserved.
Source article on WebMD

Source: MedicineNet.com
http://www.medicinenet.com/heart_failure/article.htm