Heart Failure

Also known as Congestive heart failure

Doctor using a stethoscope on a womanHeart failure is a condition that develops when your heart doesn’t pump enough blood for your body’s needs. This can happen if your heart can’t fill up with enough blood. It can also happen when your heart is too weak to pump properly. The term "heart failure" does not mean that your heart has stopped. However, heart failure is a serious condition that needs medical care. 

More than 6 million adults in the United States have heart failure, according to the Centers for Disease Control and Prevention. Children can also have heart failure, but this health topic focuses on heart failure in adults. 

Heart failure can develop suddenly (the acute kind) or over time as your heart gets weaker (the chronic kind). It can affect one or both sides of your heart. Left-sided and right-sided heart failure may have different causes. Most often, heart failure is caused by another medical condition that damages your heart. This includes coronary heart diseaseheart inflammationhigh blood pressure, cardiomyopathy, or an irregular heartbeat . Heart failure may not cause symptoms right away. But eventually, you may feel tired and short of breath and notice fluid buildup in your lower body, around your stomach, or neck. 

Heart failure can damage your liver or kidneys. Other complications include pulmonary hypertension or other heart conditions, such as an irregular heartbeatheart valve disease, and sudden cardiac arrest.  

Your doctor will diagnose heart failure based on your medical and family history, a physical exam, and results from imaging and blood tests. 

Currently, heart failure is a serious condition that has no cure. However, treatment such as healthy lifestyle changes, medicines, some devices and procedures can help many people have a higher quality of life. Visit the Living With section to learn more. 

Visit The Heart Truth to learn about heart disease in women.  

Causes - Heart Failure

Chronic (long-term) heart failure is often caused by other medical conditions that damage or overwork your heart. Acute (sudden) heart failure can be caused by an injury or infection that damages your heart, a heart attack, or a blood clot in your lung

To understand heart failure, it helps to know how the heart works. The right side of your heart gets oxygen-low blood from your body. It pumps the blood to your lungs to pick up oxygen. The left side of your heart pumps oxygen-rich blood to the rest of your body. 

This animation describes heart failure and some of its causes. Medical Animation Copyright © 2021 Nucleus Medical Media Inc. All rights reserved

What causes left-sided heart failure? 

Left-sided heart failure is more common than right-sided heart failure. There are two types of left-sided heart failure, each based on how well your heart can pump. This measurement is called the ejection fraction. Visit the Diagnosis section to learn more about the ejection fraction. 

  • In heart failure with reduced ejection fraction (HFrEF), the left side of your heart is weak and can’t pump enough blood to the rest of your body. Chronic (long-term) conditions that damage or weaken the heart muscle are the main cause of heart failure with reduced ejection fraction. For example, coronary heart disease or a heart attack can prevent your heart muscle from getting enough oxygen (shown below). Other causes of this type of heart failure include faulty heart valves, an irregular heartbeat, or heart diseases that you are born with or inherit.  

How a heart attack can lead to heart failure. Figure A shows dead heart muscle caused by a heart attack. Figure B is a close-up showing how a blocked artery in the heart prevents the heart muscle from getting oxygen. The heart muscle begins to die, weakening the heart
How a heart attack can lead to heart failure. Figure A shows dead heart muscle caused by a heart attack. Figure B is a close-up showing how a blocked artery in the heart prevents the heart muscle from getting oxygen. The heart muscle begins to die, weakening the heart
  • In heart failure with preserved ejection fraction (HFpEF), the left side of your heart is too stiff to fully relax between heartbeats. That means it can't fill up with enough blood to pump out to your body. High blood pressure and other conditions that make your heart work harder are the main causes of heart failure with preserved ejection fraction. Conditions that stiffen the chambers of the heart such as obesity and diabetes are also causes of this type of heart failure. Over time, your heart muscle thickens to adapt, which makes it stiffer. 

Visit the Diagnosis section to learn more about heart failure with preserved or reduced ejection fraction and how doctors diagnose it. 

What causes right-sided heart failure? 

Over time left-sided heart failure can lead to right-sided heart failure.  

In right-sided heart failure, your heart can't pump enough blood to your lungs to pick up oxygen. Left-sided heart failure is the main cause of right-sided heart failure. That’s because left-sided heart failure can cause blood to build up on the left side of your heart. The build-up of blood raises the pressure in the blood vessels that carry blood from your heart to your lungs. This is called pulmonary hypertension, and it can make the right side of your heart work harder.  

Congenital heart defects or conditions that damage the right side of your heart such as abnormal heart valves can also lead to right-side heart failure on its own. The same is true for conditions that damage the lungs, such as chronic obstructive pulmonary disease (COPD).  

Risk Factors - Heart Failure

Many factors can raise your risk of heart failure. Some factors you can control, such as lifestyle habits. Others you cannot, including your age, race, or ethnicity. Your risk of heart failure goes up if you have more than one of these factors. 

  • Age. People 65 years or older have a higher risk of heart failure because aging can weaken and stiffen your heart. Older adults are also more likely to have other health conditions that cause heart failure.  
  • Family history and genetics. Your risk of heart failure is higher if people in your family have been diagnosed with heart failure. Certain gene mutations can also raise your risk. These mutations make your heart tissue weaker or less flexible. 
  • Lifestyle habits. An unhealthy diet, smoking, using cocaine or other illegal drugs, heavy alcohol use, and lack of physical activity can raise your risk of heart failure. 
  • Other medical conditions. Any heart or blood vessel condition, serious lung disease, or infection such as HIV or SARS-CoV-2 may raise your risk of heart failure. Long-term health conditions such as obesityhigh blood pressurediabetessleep apnea, chronic kidney disease, anemia, thyroid disease, or iron overload also raise your risk. Cancer treatments such as radiation and chemotherapy can injure your heart and raise your risk. Atrial fibrillation, a common type of irregular heart rhythm, can also cause heart failure. 
  • ​​​​​​​Race or ethnicity. African Americans are more likely to have heart failure than people of other races. They also often have more serious cases of heart failure and at a younger age. 
  • ​​​​​​​Sex. Heart failure is common in both men and women, although men often develop heart failure at a younger age than women. Women more commonly have heart failure with preserved ejection fraction (HFpEF), which occurs when the heart does not fill with enough blood. Men are more likely to have heart failure with reduced ejection fraction (HFrEF). Women often have worse symptoms than men. 

Screening and Prevention - Heart Failure

To screen for heart failure, your doctor will determine your risk factors. If you’re at high risk, your doctor may measure your blood levels of certain molecules that rise during heart failure. Visit the Diagnosis section to learn more.  

You can take the following steps to lower your risk of developing heart failure. The sooner you start, the better your chances of preventing or delaying the condition. 

  • Adopt a heart-healthy lifestyle. Choosing heart-healthy foods, aiming for a healthy weight, getting regular physical activity, quitting smoking, and managing stress can help keep your heart healthy. 
  • Limit or avoid alcohol and do not use illegal drugs. 
  • Work with your healthcare team to manage conditions that raise your risk of heart failure, such as diabetes, high blood pressure, and obesity

Signs, Symptoms, and Complications - Heart Failure

Symptoms of heart failure depend on the type of heart failure you have and how serious it is. If you have mild heart failure, you may not notice any symptoms except during hard physical work. Symptoms can depend on whether you have left-sided or right-sided heart failure. However, you can have symptoms of both types. Symptoms usually get worse as your heart grows weaker.  

Heart failure can lead to serious and life-threatening complications. 


The image shows the major symptoms of left-sided and right-sided heart failure.
The image shows the major symptoms of left-sided and right-sided heart failure.

One of the first symptoms you may notice is feeling short of breath after routine activities like climbing stairs. As your heart grows weaker, you may notice this while getting dressed or walking across the room. Some people have shortness of breath while lying flat. 

In addition, people who have left-sided heart failure may have the following symptoms. 

  • Trouble breathing 
  • Cough 
  • Fatigue (extreme tiredness even after rest) 
  • General weakness 
  • Bluish color of finger and lips  
  • Sleepiness and trouble concentrating 
  • Inability to sleep lying flat 

Older adults who do not get much physical activity may not experience shortness of breath. But they may feel tired and confused. 

People who have right-sided heart failure may also have the following symptoms: 

  • Nausea (feeling sick in the stomach) and loss of appetite 
  • Pain in your abdomen (area around your stomach)  
  • Swelling in your ankles, feet, legs, abdomen, and veins in your neck 
  • ​​​​​​​Needing to pee often 
  • Weight gain 


Heart failure can cause the following serious complications: 

  • Kidney or liver damage because of reduced blood flow and fluid buildup in your organs 
  • ​​​​​​​Fluid buildup in or around your lungs 
  • ​​​​​​​Malnutrition because nausea and swelling in your abdomen (area around your stomach) can make it uncomfortable for you to eat. Reduced blood flow to your stomach can make it harder to absorb nutrients from your food. 
  • Other heart conditions, such as an irregular heartbeat, leaking heart valves , or sudden cardiac arrest 
  • Pulmonary hypertension 


Diagnosis - Heart Failure

Your doctor will diagnose heart failure based on your medical history, a physical exam, and test results. Your doctor may also refer you to a cardiologist for these tests and treatment. A cardiologist is a doctor who specializes in diagnosing and treating heart diseases. 

Medical history and physical exam 

Bring a list of your symptoms to your doctor’s appointment, including how often they happen and when they started. Also, bring a list of any prescription and over-the-counter medicines you take. Let your doctor know if you have any risk factors for heart failure. 

During your physical exam, your doctor will: 

  • Measure your heart rate, blood pressure, and body weight. 
  • Listen to your heart with a stethoscope for sounds that suggest that your heart is not working properly. 
  • Listen to your lungs for the sounds of fluid buildup. 
  • Look for swelling in your ankles, feet, legs, liver, and veins in your neck. 

Diagnostic tests and procedures 

This animation discusses some of the tests used to diagnose heart failure. These tests may include an electrocardiogram to look at your heart’s electrical activity, an echocardiogram to measure how well your heart is working and look at the structure, and a chest X-ray to see if your heart is enlarged or there is fluid in your lungs. Other tests may include blood tests and an exercise, or stress test. Medical Animation Copyright © 2021 Nucleus Medical Media Inc. All rights reserved

Blood tests 

Your doctor may order blood tests to check the levels of certain molecules, such as brain natriuretic peptide (BNP). These levels rise during heart failure. Blood tests can also show how well your liver and your kidneys are working. 

Tests to measure your ejection fraction 

Your doctor may order an echocardiography (echo) or other imaging tests to measure your ejection fraction. Your ejection fraction is the percent of the blood in the lower left chamber of your heart (the left ventricle) that is pumped out of your heart with each heartbeat. Ejection fraction tells your doctor how well your heart pumps. This helps your doctor diagnose the type of heart failure you have and guide your treatment. 

  • If 40% or less of the blood in your left ventricle is pumped out in one beat, you have heart failure with reduced ejection fraction. 
  • If 50% or more of the blood in your left ventricle is pumped out in one beat, you have heart failure with preserved ejection fraction. 

If your ejection fraction is somewhere in between (41% to 49%), you may be diagnosed with heart failure with borderline ejection fraction. 

Other tests 

  • Other imaging tests to show how well your heart is working, such as a cardiac CT scancardiac MRI, or nuclear heart scan. To look inside the arteries in your heart to see if they are blocked, you may also need cardiac catheterization with coronary angiography
  • Tests for your heart’s electrical activity, including an electrocardiogram (EKG) or a Holter or event monitor that you wear for 24 to 48 hours or longer while going about your normal activities. 
  • stress test to measure how much exercise your body can handle and how well it works during physical activity. Some heart problems are easier to diagnose when your heart is working hard and beating fast. 

Treatment - Heart Failure

Heart failure has no cure. But treatment can help you live a longer, more active life with fewer symptoms. Treatment depends on the type of heart failure you have and how serious it is but usually includes heart-healthy lifestyle changes and medicines. You may need a procedure or surgery for some types of serious heart failure. Because heart failure often gets worse over time, it is important for you and your caregivers to discuss your long-term treatment goals with your healthcare team. 

Your healthcare team will also treat any medical condition that caused or worsens your heart failure. 

This video describes possible treatments for heart failure, including lifestyle changes, medicines such as diuretics to get rid of excess fluid, or a heart procedure or surgery. Medical Animation Copyright © 2021 Nucleus Medical Media Inc. All rights reserved

Your healthcare team may include a cardiologist (a doctor who specializes in treating heart conditions), nurses, your primary care doctor, pharmacists, a dietitian, physical therapists and other members of your cardiac rehabilitation team, and social workers. 

Healthy lifestyle changes 

Your doctor may recommend these heart-healthy lifestyle changes alone or as part of a cardiac rehabilitation plan: 

  • Lower your sodium (salt) intake. Salt may make your fluid buildup worse. View our Tips To Reduce Salt and Sodium fact sheet. 
  • Aim for a healthy weight since extra weight can make your heart work harder. 
  • Get regular physical activity. Ask your doctor about how active you should be, including during daily activities, work, leisure time, sex, and exercise. Your level of activity will depend on how serious your heart failure is. Sometimes, your healthcare provider might recommend outpatient cardiac rehabilitation services to improve what level of exercise you can do and reduce your risk factors.  
  • Quit smoking. View Smoking and Your Heart for more information. For free help quitting smoking, you may call the National Cancer Institute’s Smoking Quitline at 1-877-44U-QUIT (1-877-448-7848). 
  • Avoid or limit alcohol. Your doctor may recommend that you limit or stop drinking alcohol. You can find resources and support at the National Institute on Alcohol Abuse and Alcoholism’s Alcohol Treatment Navigator
  • Manage contributing risk factors. Controlling some of the factors that may worsen heart failure like blood pressure, heart rhythm, and anemia will often improve heart health.  
  • Manage stress. Learning how to manage stress and cope with problems can improve your mental and physical health. Learning relaxation techniques, talking to a counselor, and finding a support group can all help. Visit Relaxation Techniques for Health to learn more about how relaxation techniques can help lower stress and anxiety. 
  • Get good-quality sleep. Sleep disorders such as sleep apnea are common in people who have heart failure. Treating your sleep disorder helps improve your sleep and may help improve your heart failure symptoms. 

Learn more about these healthy lifestyle changes in our Heart-Healthy Living Health Topic.  


Your doctor may prescribe medicines based on the type of heart failure you have, how serious it is, and your response to certain medicines. 

Left-sided heart failure 

The following medicines are commonly used to treat heart failure with reduced ejection fraction. 

  • Medicines to remove extra sodium and fluid from your body, including diuretics and aldosterone antagonists (such as spironolactone). These medicines lower the amount of blood that the heart must pump. Very high doses of diuretics may cause low blood pressure, kidney disease, and worsening heart failure symptoms. Side effects of aldosterone antagonists can include kidney disease and high potassium levels. 
  • Medicine to relax your blood vessels to make it easier for your heart to pump blood. Examples include angiotensin converting enzyme inhibitors and angiotensin receptor blockers. Possible side effects include cough, low blood pressure, and short-term reduced kidney function.  
  • Medicines to slow your heart rate, such as beta blockers and ivabradine. These medicines make it easier for your heart to pump blood and can help prevent long-term heart failure from getting worse. Possible side effects include a slow or irregular heart rate, high blood pressure, and fuzzy vision or seeing bright halos. 
  • Newer medications. Two new groups of medicines approved to lower blood sugar in patients with diabetes, sodium-glucose cotransporter-2 (SGLT-2) inhibitors and glucagon-like peptide (GLP) agonists, may also reduce heart failure hospitalizations. Their use in treating heart failure is currently being studied. 
  • Digoxin to make your heart beat stronger and pump more blood. This medicine is mostly used to treat serious heart failure when other medicines do not help improve your symptoms. Side effects may include digestive problems, confusion, and vision problems. 

Currently, the main treatment for heart failure with preserved ejection fraction are diuretics. Your doctor also may prescribe blood pressure medicines to help relieve your symptoms

Right-sided heart failure 

If you have right-sided heart failure, your doctor may prescribe medicines to remove extra sodium and fluid from your body, and medicines to relax your blood vessels. 

Procedures and surgeries 

If your heart failure with reduced ejection fraction worsens, you may need one of the following medical devices:  

You may also need heart surgery to repair a congenital heart defect or damage to your heart. If your heart failure is life-threatening and other treatments have not worked, you may need a heart transplant

For people with heart failure and preserved ejection fraction, there are no currently approved devices or procedures to improve symptoms. Researchers are continuing to study possible treatments.  

Living With - Heart Failure

If you have heart failure, you will likely have to follow a treatment plan for the rest of your life. Even with treatment, heart failure often gets worse over time. However, you can take steps to have a higher quality of life. 

Manage your condition 

Following your treatment plan can help relieve symptoms and make daily activities easier. It also can lower the chance that you’ll have to go to the hospital. 

  • Take your medicines as your doctor prescribes. Tell your doctor if you have side effects from any of your medicines. He or she might adjust the dose or change the type of medicine you take to reduce side effects. 

  • Make heart-healthy lifestyle changes recommended by your doctor. Habits can be hard to change. Let your doctor know if you’re having a hard time sticking with any of the changes. Your doctor may ask you to limit the amount of salt and liquids that you drink to reduce fluid buildup. 
  • Get medical care for other conditions that can worsen heart failure. These include obesity, diabetes, high blood pressuresleep apnea, and lung, kidney, or liver disease. Tell your doctor and pharmacist about all the medicines you’re taking. Taking medicines together can raise the risk of side effects. Also, certain medicines can worsen your heart failure symptoms. 

Know when to seek help 

Watch for signs that heart failure is getting worse, such as new or worsening symptoms. Weight gain, ankle swelling, or increasing shortness of breath may mean that fluids are building up in your body. Ask your doctor how often you should check your weight and when to report weight changes. 

Your symptoms may suddenly get worse. Ask your doctor when to make an office visit or get emergency care. Keep the following handy: 

  • Phone numbers for your doctor, the hospital, and someone who can take you for medical care  
  • Directions to the doctor's office and hospital  
  • A list of all the medicines you’re taking  

Get support and know your options 

Living with heart failure may cause fear, anxiety, depression, and stress. Talk to your healthcare team or a professional counselor. They can help you find or learn ways to cope. 

  • Get treatment for depression. If you are depressed, your doctor may recommend medicines or other treatments that can improve your quality of life. 
  • Join a patient support group. You can learn how other people who have similar symptoms have coped with them. Your doctor may be able to help you find local support groups, or you can check with an area medical center. 
  • ​​​​​​​Seek support from family and friends. Letting your loved ones know how you feel and what they can do to help can help lower your stress and anxiety. 
  • Know your treatment options. If your heart failure is very serious, palliative or hospice care can improve your quality of life and help make your daily life more comfortable. This type of care focuses on managing your symptoms, helping you avoid unnecessary tests or treatments, and providing support to your loved ones. 

Participate in NHLBI Clinical Trials

We lead or sponsor many studies on heart failure. See if you or someone you know is eligible to participate in our clinical trials and observational studies

Trials at the NIH Clinical Center

New treatments for functional mitral valve regurgitation

This study will test a new method to treat functional mitral valve regurgitation, which is a heart condition that can cause heart failure. In this study, researchers will insert a device into the heart to fix damaged valves and help prevent heart failure. To participate in this study, you must be at least 21 years old and have serious functional mitral valve regurgitation. This study is located in Bethesda, Maryland.

Developing new cardiovascular MRI imaging techniques for heart diseases

This study is comparing how well two types of magnetic resonance imaging (MRI) scanners can detect different types of heart diseases, such as coronary heart disease, heart failure, congenital heart disease, and heart valve disease. The new type of MRI scanner in this study uses less energy than a traditional scanner and may be suitable for people who have metal devices in their bodies. To participate in this study, you must be healthy or have stable coronary heart disease and be at least 18 years old. This study is located in Bethesda, Maryland.

To learn more about clinical trials at the NIH Clinical Center or to talk to someone about a study that might fit your needs, call the Office of Patient Recruitment 800-411-1222.

Are you a healthy adult, or do you have pulmonary hypertension and heart failure?

This study is comparing how a medicine called oral nitrate gets broken down in healthy adults and in adults who have pulmonary hypertension and heart failure with preserved ejection fraction. Oral nitrate is a medicine used to improve blood flow for certain heart conditions. Participants will provide blood, stool, saliva, and urine samples and have their vitals checked at several points in the study. This research will help reveal how oral nitrate affects oral and gut bacteria. To participate in this study, you must be at least 18 years old and either be healthy or have pulmonary hypertension and heart failure that was confirmed by right-heart catheterization in the past 6 months. This study is located in Pittsburgh, Pennsylvania.

Do you have heart failure with reduced ejection fraction and thyroid problems?

This study will test whether hormone therapy with liothyronine is safe and effective for treating people who have heart failure with reduced ejection fraction and low triiothyronine (T3) syndrome. Low T3 syndrome is a type of thyroid hormone that helps control many functions of your body. To participate in this study, you must be at least 18 years old and diagnosed with heart failure with reduced ejection fraction. This study is located in Philadelphia, Pennsylvania.

Are you at least 21 years old, and do you have heart failure?

This study aims to better understand why heart failure can make it hard to exercise and perform daily activities. This complication is called exercise intolerance. Participants in the study will complete physical activities and then undergo magnetic resonance imaging (MRI) to look for changes in the chemicals the body uses for energy. To participate in this study, you must be at least 21 years old, diagnosed with heart failure, and be medically stable. This study is located in Baltimore, Maryland.
View more information about Exercise Intolerance in Heart Failure.

Are you interested in exercise training for your heart failure with preserved ejection fraction?

This study aims to test whether a medicine called sodium nitrite can help reduce exercise intolerance in people who have heart failure with preserved ejection fraction. Exercise intolerance occurs when a person is unable to exercise at a normal level or length of time. You will be randomized to receive either sodium nitrate or a placebo while taking part in cardiac rehabilitation for exercise training. To participate in this study, you must be at least 40 years old, diagnosed with heart failure with preserved ejection fraction, and have shortness of breath. This study is located in Rochester, Minnesota.

Are you a professional caregiver for an adult who has serious heart failure?

This study is testing whether electronic educational resources, in addition to in-person training , help home aids be more knowledgeable and confident in caring for adults who have serious heart failure. To participate in this study, you must be between 18 and 75 years old, be employed at Visiting Nurse Service of New York's Partners in Care agency, and care for an adult who has heart failure. This study is located in New York, New York.

Metabolic Mapping and Cardiac Resynchronization

This study will test whether a type of pacemaker called a cardiac resynchronization device can help the heart pump more blood in people who have mild heart failure (HF) and left bundle branch block. In the study, participants will have a cardiac resynchronization device implanted. To participate in this study, you must be at least 18 years old and have mild heart failure and a left bundle branch block.

Are you an adult with pulmonary hypertension and normal pump function of your heart?

This study is looking at the effect of an oral medicine called a nitrate on the ability to exercise in people who have pulmonary hypertension and normal pump function of their heart, also known as pulmonary hypertension and heart failure with preserved ejection fraction (PH-HFpEF). To participate in this study, you must be at least 18 years old and have PH-HFpEF that was confirmed by right heart catheterization. This study is located in Pittsburgh, Pennsylvania.

Do you want to help find new treatments for heart failure with preserved ejection fraction?

This study is testing whether a medicine called spironolactone can help treat heart failure with preserved ejection fraction when paired with the standard treatment. Spironolactone helps to remove excess water and sodium from the body. To participate in this study, you must be between 50 and 99 years old and diagnosed with heart failure with preserved ejection fraction. This study has 81 locations in the United States and Sweden.

Do you have heart failure and depression?

This study aims to see whether stepped care for depression helps people who have heart failure manage their care (follow heart-healthy lifestyle recommendations and take their prescribed medicines). Participants will either receive usual care for depression or take part in cognitive behavioral therapy, where they work with a mental health counselor to learn ways to manage symptoms and cope with challenging situations. Certain participants may then be referred for antidepressant medicines. All participants will then receive heart failure education. To participate in this study, you must be at least 25 years old and diagnosed with heart failure and major depressive disorder. This study is located in Saint Louis, Missouri.

Are you or a loved one hospitalized with serious heart failure?

This study is comparing the effectiveness of two medicines, torsemide and furosemide, in treating serious heart failure in patients who are hospitalized. Torsemide and furosemide are medicines used to treat heart failure by removing excess water in the body. To participate in this study, you must be at least 18 years old and hospitalized because of serious heart failure. This study has 56 locations across the United States.

More Information

Find additional information about Heart Failure in the following resources.