What are the stages of heart failure?
- Reviewed by Christopher P. Cannon, MD, Editor in Chief, Harvard Heart Letter; Editorial Advisory Board Member, Harvard Health Publishing
Heart failure is a progressive condition, meaning that it can worsen over time. But it also can improve after treatment. Understanding what stage of heart failure you are in can help your doctor better select effective treatment.
What is congestive heart failure?
Heart failure (HF), which used to be termed congestive heart failure, is a chronic medical condition in which the heart is unable to pump blood effectively to meet the body's needs. As a result, the body may not get the oxygen it needs for optimal functioning.
Contrary to its name, heart failure does not mean that the heart has completely stopped working.
Heart failure is often 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)
- heart attack
- cardiac arrhythmias (problems with heart rate and/or heart rhythm)
- exposure to toxins, including excessive alcohol.
What are the four stages of heart failure?
Heart failure is often classified into stages that measure a person's overall heart function and severity of symptoms. These symptoms include:
- shortness of breath, with exertion or when lying flat in bed
- swelling in the ankles (edema)
- fatigue.
ACC/AHA stages of heart failure
One commonly used staging system was developed by the American College of Cardiology (ACC) and the American Heart Association (AHA).
The four stages of heart failure as defined by the ACC and the AHA are described in the table below.
ACC/AHA stages of heart failure |
|
|
Stage A: At risk for heart failure |
|
|
Stage B: Pre-heart failure |
|
|
Stage C: Symptomatic heart failure |
|
|
Stage D: Advanced heart failure |
|
NYHA classification of heart failure
If you are diagnosed with ACC/AHA stage C or D (symptomatic or advanced) heart failure, your doctor may use the New York Heart Association (NYHA) Functional Classification to further assess your condition based on functional limitations caused by your heart failure. The NYHA classification system is described in the table below.
NYHA classification of heart failure |
|
|
Class 1 |
|
|
Class 2 |
|
|
Class 3 |
|
|
Class 4 |
|
Classification based on ejection fraction
A third way to classify heart failure is based on the ejection fraction, which measures the strength and functioning of the heart muscle.
Ejection fraction is the fraction (expressed as a percentage) of the blood that your heart "ejects" out to the rest of your body each time it contracts. For example, an ejection fraction of 60% means that each time your heart beats, 60% of the blood in the main pumping chamber (the left ventricle) is squeezed out by the heart muscle contracting.
A normal ejection fraction is about 50% to 70%. An ejection fraction between around 40% and 50% is considered borderline low. Sometimes, this reflects heart muscle that was weaker but is now recovering. Other times, a slow decline in heart muscle function is to blame. Anything below 40% means the heart is struggling to provide sufficient blood to the body.
If someone has symptoms of HF but a normal ejection fraction, this is called heart failure with preserved ejection fraction (HFpEF). If the ejection fraction is less than 40%, this is called heart failure with reduced ejection fraction (HFrEF). And if the ejection fraction is in the middle (40% to 49%), this is called heart failure with mildly reduced ejection fraction (HFmrEF).
Classification based on ejection fraction |
||
|
Ejection fraction |
Symptoms of HF? |
HF type |
|
50-70% (or greater) |
No |
No HF |
|
50-70% (or greater) |
Yes |
HFpEF |
|
40-50% |
Yes |
HFmrEF |
|
<40% |
Yes |
HFrEF |
Why is it important for patients to know what stage of heart failure they have?
The staging systems help your doctor determine the appropriate treatment and management strategy, based on how your heart is functioning and the severity of your symptoms at any given time. This, in turn, can help you understand why your doctor is prescribing a particular treatment, which symptoms are important to share with your doctor, and how your condition might progress.
Heart failure treatment focuses on
- reducing symptoms
- decreasing hospitalizations
- improving life expectancy.
Based on your stage of heart failure, your doctor will work with you to develop an ongoing treatment plan that may include lifestyle changes, medications, devices, or surgical procedures.
Many recent advances in heart failure treatment can improve ejection fraction and functional limitations caused by the condition. Speak to your doctor about what class and type of heart failure you have to help ensure you are getting the most effective treatment.
About the Author
Jenette Restivo, Health Writer; Assistant Director for Digital Content Creation and Engagement, Harvard Health Publishing
About the Reviewer
Christopher P. Cannon, MD, Editor in Chief, Harvard Heart Letter; Editorial Advisory Board Member, Harvard Health Publishing
Disclaimer:
As a service to our readers, Harvard Health Publishing provides access to our library of archived content. Please note the date of last review or update on all articles.
No content on this site, regardless of date, should ever be used as a substitute for direct medical advice from your doctor or other qualified clinician.
