Heart Failure: The Basics

Heart failure affects about 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.

What Is Heart Failure?

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. This helps to keep the blood moving, 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. Congestive heart failure is the term used to describe this condition

What Causes Heart Failure?

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

• 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, the heart becomes starved for oxygen and nutrients. This condition along with heart attack is responsible for two thirds of heart failure cases in the U.S.
• 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.
• "Non-ischemic" cardiomyopathy: This condition occurs when there is 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: High blood pressure (hypertension), valve disease, thyroid disease, kidney disease, diabetes or heart defects present at birth can all cause heart failure (some of these are non-ischemic cardiomyopathy - see above). In addition, heart failure can occur when several diseases or conditions are present at once.

What Are the Symptoms of Heart Failure?

The symptoms of heart failure are related to the changes that occur to your heart and body, and may be moderate to severe, depending on how weak your heart is. The symptoms can include:

• Congested lungs. Fluid back up in the lungs can cause shortness of breath with exercise or difficulty breathing at rest which is often worse when lying flat in bed. Lung congestion can also cause a dry, hacking cough or wheezing.
• Fluid and water retention. Less blood to your kidneys causes fluid and water retention, resulting in swollen ankles, legs and abdomen (called edema) and weight gain. Symptoms may cause an increased need to urinate during the night. Bloating in your stomach may cause a loss of appetite or nausea.
• Dizziness, fatigue and weakness. Less blood to your major organs and muscles makes you feel tired and weak. Less blood to the brain can cause dizziness or confusion.
• Rapid or irregular heartbeats. The heart beats faster to pump enough blood to the body. This can cause a fast or irregular heartbeat.

If you have heart failure, you may have one or all of these symptoms or you may have none of them. In addition, your symptoms may not be related to how weak your heart is; you may have many symptoms but your heart function may be only mildly weakened. Or you may have a more severely damaged heart but have no symptoms.