Types of Heart Failure

Common questions
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Bring this list of questions about treating heart failure to your next appointment with your doctor—and be sure to take notes during your conversation.



Find definitions of technical terms in our glossary.

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about types of heart failure from the American Heart Association.

Right- and Left-Sided Heart Failure

Treatment for heart failure depends on the type of heart failure you have. In some types, the heart does not fill with enough blood. In others, the heart cannot pump with enough force to send blood to the whole body. Most often, heart failure begins with the left ventricle, which is your heart’s primary pumping chamber. It can also involve the right side or, in some cases, both sides of your heart. 

Left-sided heart failure

The left ventricle of the heart is larger than the right ventricle and does most of the heart’s pumping work. When left-sided heart failure occurs, the left ventricle (lower chamber) of the heart must work harder to pump the same amount of blood.

There are two types of left-sided heart failure:

  • Preserved ejection fraction (HFpEF), also called diastolic heart failure—the heart muscle contracts normally but the ventricles do not relax as they should during ventricular filling (or when the ventricles relax).
  • Reduced ejection fraction (HFrEF), also called systolic heart failure —the heart muscle does not contract effectively and less oxygen-rich blood is pumped out to the body.

Read more about ejection fraction:

 Ejection fraction (EF) information from heart.org

Right-sided heart failure 

This type of heart failure affects the right side, or right ventricle, of the heart. It usually results from left-sided heart failure, but it can also be a result of damage to the right ventricle from a heart attack. When the left ventricle fails, increased fluid pressure is forced back through the lungs, damaging the heart’s right side. With the right-side loss of pumping power, blood backs up in the veins, often causing swelling in the body, such as in the ankles and legs.

Congestive heart failure

Congestive heart failure takes place when the veins near the heart become “congested,” or full of blood. As blood flow from the heart slows down, blood gets trapped in the veins on its way back to the heart, causing edema (swelling). The swelling usually occurs in the legs and ankles. Heart failure also affects the kidneys’ ability to flush water and sodium from the body, which causes even more swelling. 

Classes, or stages, of heart failure

Heart failure is classified by how severe it is. These four classes of heart failure have been defined by the New York Heart Association.

  • Class I (No Symptoms): You can keep up your physical activities as usual. 
  • Class II (Mild): Your physical activity is slightly limited. You are comfortable when sitting or resting, but ordinary activity causes fatigue, palpitations (feeling that your heart is pounding or racing) or shortness of breath.
  • Class III (Moderate): Your physical activity becomes more limited. You are comfortable when sitting or resting, but activity causes fatigue, palpitations or shortness of breath.
  • Class IV (Severe): You experience shortness of breath with any physical activity and when sitting or resting, you may feel fatigue, cough, shortness of breath and chest pain.