Overview

Heart failure occurs when the heart muscle doesn't pump blood as well as it should. When this happens, blood often backs up and fluid can build up in the lungs, causing shortness of breath.

Some heart conditions cause the heart to become too weak or stiff to fill and pump blood properly. These conditions include narrowed arteries in the heart and high blood pressure.

Proper treatment may improve the symptoms of heart failure and may help some people live longer. Lifestyle changes can improve quality of life. Try to lose weight, exercise, use less salt and manage stress.

But heart failure can be life-threatening. People with heart failure may have severe symptoms. Some may need a heart transplant or a device to help the heart pump blood.

Heart failure also may be called congestive heart failure. The term "congestive" refers to fluid buildup in the lungs or other parts of the body. You also may see the term "cardiac failure" used to mean heart failure.

In the United States, congestive heart failure is a common condition.

Heart failure care at Mayo Clinic

Types

Healthcare professionals may describe congestive heart failure by:

  • Which side of the heart is affected.
  • How well the heart squeezes or relaxes.
  • Whether symptoms started suddenly or have been present for a long time.
  • Whether the heart is affected by blockages or vessel narrowing or a different cause.

These things help guide testing and treatment.

There are different types of heart failure.

  • Left-sided heart failure. This type affects the lower left heart chamber, called the left ventricle. This is the heart's main pumping chamber. Fluid may back up in the lungs, causing shortness of breath. This shortness of breath can occur when walking, sitting, lying down or bending over, and even at rest.
  • Right-sided heart failure. This type affects the lower right chamber, called the right ventricle. Fluid may back up into the belly, legs and feet, causing swelling in the legs or belly or nausea and bloating.

Sometimes, heart failure affects both sides of the heart.

Heart failure also may be described by how much blood the lower left heart chamber pumps out with each squeeze. This is called the ejection fraction (EF). Ejection fraction also helps determine the type of heart failure and guide treatment.

  • In heart failure with preserved ejection fraction (HFpEF), the ejection fraction is 50% or higher. But the heart still may not pump enough blood to meet the body's needs. HFpEF is a type of left-sided heart failure. It also may be called diastolic heart failure. The left ventricle can't relax, and the heart has trouble filling with blood.
  • In heart failure with reduced ejection fraction (HFrEF), the ejection fraction is often 40% or lower. HFrEF is a type of left-sided heart failure. It also may be called systolic heart failure. The left ventricle can't squeeze as well as it should. The heart isn't strong enough to pump enough blood to the body.

Chronic, acute and decompensated heart failure

You also may hear the terms "chronic," "acute" and "decompensated." They describe when heart failure begins or how it changes.

  • Chronic heart failure. It continues over time. Symptoms may be stable for a while and then get worse.
  • Acute heart failure. It starts suddenly or gets worse quickly. It needs prompt medical care.
  • Acute decompensated heart failure. This is a sudden or gradual worsening of chronic heart failure. It often needs added treatment in a hospital.

End-stage or advanced heart failure

During end-stage congestive heart failure, you may have severe symptoms that interfere with daily life. Symptoms may occur while you are resting or with very little activity. The symptoms continue despite treatment. Some people with advanced heart failure cannot tolerate standard medicines.

Products & Services

Symptoms

If you have congestive heart failure, your heart can't supply enough blood to meet your body's needs.

Symptoms may develop slowly. Sometimes, heart failure symptoms start suddenly. Heart failure symptoms may include:

  • Shortness of breath with activity, when lying down, when bending over or even at rest. Shortness of breath also is called dyspnea.
  • Fatigue and weakness.
  • Swelling in the legs, ankles and feet.
  • Fast or irregular heartbeat.
  • Reduced ability to exercise.
  • Wheezing.

Other symptoms may include:

  • A cough that doesn't go away or a cough that brings up white or pink mucus with spots of blood.
  • Swelling of the belly area, causing nausea, bloating or a sensation of fullness.
  • Very fast weight gain from fluid buildup.
  • Nausea and lack of appetite.
  • Trouble concentrating or decreased alertness.
  • Chest pain if heart failure is caused by a heart attack.

These symptoms can be caused by many different health conditions. A complete checkup by a healthcare professional is needed to make a diagnosis.

Symptoms of end-stage or advanced heart failure

Symptoms that heart failure may be at an advanced stage include:

  • Shortness of breath with very little activity or at rest.
  • Swelling that is hard to control and requires higher doses or additional medicines called diuretics.
  • Low blood pressure or worsening kidney or liver function.
  • Repeated hospital stays or ER visits, dangerous heartbeats, or repeated shocks from an implantable cardioverter-defibrillator (ICD).
  • Difficulty tolerating heart failure medicines, which may require lowering the dose or stopping some medicines because of problems such as low blood pressure or worsening kidney function.

These symptoms cannot tell exactly how long someone will live. If you have advanced heart failure, your care team can talk with you about treatment choices and what matters to you.

When to seek care

See your healthcare professional if you think you might have symptoms of heart failure.

Call your healthcare professional right away if you have heart failure and:

  • Your symptoms suddenly get worse.
  • You develop a new symptom.
  • You gain 5 pounds (2.3 kilograms) or more within a few days.

These changes could mean that heart failure is getting worse or that treatment isn't working.

Follow the action plan from your healthcare professional. It may give a different weight-change limit or other instructions based on your condition.

When to seek emergency care

Call 911 or your local emergency number if you have any of the following:

  • Chest pain.
  • Fainting or severe weakness.
  • Fast or irregular heartbeat with shortness of breath, chest pain or fainting.
  • Repeated shocks from a defibrillator if you have one.
  • Sudden, severe shortness of breath and coughing up white or pink foamy mucus.

These symptoms may be due to heart failure. But there are many other possible causes. Don't try to diagnose yourself.

In the emergency room (ER), healthcare professionals do tests to learn whether your symptoms are due to heart failure or something else.

Get the latest heart transplant-related health information from Mayo Clinic.

Sign up for free, and receive heart transplant and heart failure content, plus expertise on heart health.

Location

We use the data you provide to deliver you the content you requested. To provide you with the most relevant and helpful information, we may combine your email and website data with other information we have about you. If you are a Mayo Clinic patient, we will only use your protected health information as outlined in our Notice of Privacy Practices. You may opt out of email communications at any time by clicking on the unsubscribe link in the email.

Causes

Heart failure can be caused by a weakened, damaged or stiff heart.

  • If the heart is damaged or weakened, the heart chambers may stretch and get bigger. The heart can't pump out the needed amount of blood.
  • If the main pumping chambers of the heart, called the ventricles, are stiff, they can't fill with enough blood between beats.

The heart muscle can be damaged by certain infections, heavy alcohol use, recreational drug use and some chemotherapy medicines.

Any of the following conditions also can damage or weaken the heart and cause heart failure.

  • Coronary artery disease and heart attack. Coronary artery disease is the most common cause of heart failure. The disease results from the buildup of fatty deposits in the arteries. The deposits narrow the arteries. This reduces blood flow and can lead to heart attack.

    A heart attack occurs when blood flow to part of the heart is blocked. Damage to the heart muscle from a heart attack may mean that the heart can no longer pump as well as it should.

  • High blood pressure. Also called hypertension, this condition forces the heart to work harder than it should to pump blood through the body. Over time, the extra work can make the heart muscle too stiff or too weak to properly pump blood.
  • Heart valve disease. The valves of the heart keep blood flowing the right way. If a valve isn't working properly, the heart must work harder to pump blood. This can weaken the heart over time. Treating some types of heart valve disease may reverse heart failure.
  • Inflammation of the heart muscle, also called myocarditis. Myocarditis is caused most commonly by a virus, including the COVID-19 virus. Myocarditis can lead to left-sided heart failure.
  • Disease of the heart muscle, called cardiomyopathy. There are different types of cardiomyopathy. In general, the condition causes the heart to have a harder time pumping blood to the rest of the body. This can lead to symptoms of heart failure.
  • A heart condition that you're born with, also called a congenital heart defect. Congenital heart defects affect both children and adults. If the heart and its chambers or valves haven't formed correctly, the other parts of the heart have to work harder to pump blood. This may lead to heart failure.
  • Irregular heartbeats, called arrhythmias. Irregular heartbeats may cause the heart to beat too fast, creating extra work for the heart. A slow heartbeat also may lead to heart failure. Treating an arrhythmia may reverse heart failure in some people.
  • Other diseases. Some long-term diseases may contribute to chronic heart failure. Examples are diabetes, HIV infection, an overactive or underactive thyroid, or a buildup of iron or protein.

Your genes also can play a role. Some conditions that cause heart failure, including hypertrophic cardiomyopathy, may be inherited but not all are. Ask your healthcare professional whether genetic counseling or testing may be helpful if several relatives have had heart failure or cardiomyopathy.

Causes of sudden or worsening heart failure also include:

  • A heart attack or reduced blood flow to the heart.
  • Allergic reactions.
  • A severe infection, such as pneumonia.
  • A blood clot in the lungs, called a pulmonary embolism.
  • Very high blood pressure.
  • A sudden heart valve issue.

Other causes include:

  • Any illness that affects the whole body.
  • Viruses that attack the heart muscle.
  • A fast or irregular heartbeat.
  • Missing heart failure medicines or taking a medicine that can worsen heart failure.
  • Having too much sodium or fluid.
  • Use of some medicines, including some chemotherapy medicines to treat cancer.

Risk factors

Heart and blood vessel conditions that increase the risk of heart failure or make existing heart failure worse include:

  • Coronary artery disease. Narrowed arteries may limit the heart's supply of oxygen-rich blood, resulting in weakened heart muscle.
  • Heart attack. A heart attack is a form of coronary artery disease that occurs suddenly. Damage to the heart muscle from a heart attack may mean the heart can no longer pump as well as it should.
  • Heart valve disease. Having a heart valve that doesn't work properly raises the risk of heart failure.
  • High blood pressure. The heart works harder than it has to when blood pressure is high.
  • Irregular heartbeats. Irregular heartbeats, especially if they are very frequent and fast, can weaken the heart muscle and cause heart failure.
  • Congenital heart disease. Some people who develop heart failure were born with changes in the structure or function of their heart.

Other health conditions that may increase the risk of heart failure or make it worse include:

  • Diabetes. Having diabetes increases the risk of high blood pressure and coronary artery disease.
  • Sleep apnea. This condition causes breathing to repeatedly stop and start during sleep. It can lower blood oxygen levels and raise the risk of irregular heartbeats. Obstructive and central sleep apnea can worsen heart failure, including right-sided heart failure.
  • Obesity. People who have obesity have a higher risk of developing heart failure.
  • Viral infections, including COVID-19. Some viral infections can injure the heart and cause myocarditis, irregular heartbeats or heart failure. They also may worsen existing heart failure.
  • Stroke. A stroke can affect signals between the brain and heart. Some people have irregular heartbeats or changes in how the heart squeezes or relaxes after a stroke. Heart failure can sometimes occur, but it does not happen to everyone who has a stroke.
  • Pneumonia and other respiratory infections. These infections can trigger or worsen heart failure. They also can cause shortness of breath, so tests may be needed to find the cause.
  • Anorexia nervosa. This eating disorder is linked with a higher risk of heart failure and other heart conditions.

Medicines that may increase the risk of heart failure or make it worse include:

  • Some diabetes medicines. The diabetes medicines rosiglitazone and pioglitazone (Actos) have been found to increase the risk of heart failure in some people. Don't stop taking these medicines without first talking to your healthcare professional.
  • Some other medicines. Other medicines that may lead to heart failure or heart conditions include nonsteroidal anti-inflammatory drugs (NSAIDs) and some medicines used to treat high blood pressure, cancer, blood conditions, irregular heartbeats, nervous system diseases, mental health conditions, lung and urinary conditions, and infections.

Other risk factors for heart failure include:

  • Aging. The heart's ability to work decreases with age, even in healthy people.
  • Alcohol use. Drinking too much alcohol may weaken the heart muscle and lead to heart failure.
  • Drugs, including amphetamines and alcohol.
  • Smoking or using tobacco. If you smoke, quit. Using tobacco increases the risk of heart disease and heart failure.

Complications

If you have heart failure, it's important to have regular health checkups, even if symptoms improve. Your healthcare professional can examine you and run tests to check for complications.

Complications of heart failure depend on your age, overall health and the severity of heart disease. They may include:

  • Kidney damage or failure. Heart failure can reduce the blood flow to the kidneys. Untreated, this can cause kidney failure. Kidney damage from heart failure can require dialysis for treatment.
  • Other heart changes. Heart failure can cause changes in the heart's size and function. These changes may damage heart valves and cause irregular heartbeats.
  • Liver damage. Heart failure can cause fluid buildup that puts too much pressure on the liver. This fluid backup can lead to scarring, which makes it more difficult for the liver to work properly.
  • Sudden cardiac death. If the heart is weak, there is a risk of dying suddenly due to a dangerous irregular heartbeat.

Prevention

One way to prevent heart failure is to treat and manage the conditions that can cause heart failure or increase the risk. These conditions include coronary artery disease, high blood pressure, diabetes and obesity.

Some of the same lifestyle changes used to manage heart failure also may help prevent it. Try these heart-healthy tips:

  • Don't smoke.
  • Get plenty of exercise.
  • Eat healthy foods.
  • Maintain a healthy weight.
  • Reduce and manage stress.
  • Take medicines as directed.

Sept. 25, 2026

Living with heart failure?

Connect with others like you for support and answers to your questions in the Heart & Blood Health support group on Mayo Clinic Connect, a patient community.

Heart & Blood Health Discussions

teatime
Stopping Carvedilol (Coreg): When will the effects wear off?

419 Replies Sat, Sep 26, 2026

mcphee
High Coronary Calcium Score: How do others feel emotionally?

697 Replies Thu, Sep 17, 2026

pop77
Living with high calcium score

118 Replies Sat, Sep 12, 2026

See more discussions
  1. Ali A, et al. Prognostic value of quality of life and functional status in patients with heart failure: A systematic review and meta-analysis. The Egyptian Heart Journal. 2024; doi:10.1186/s43044-024-00532-z.
  2. Armstrong PW, et al. Vericiguat in patients with heart failure and reduced ejection fraction. New England Journal of Medicine. 2020; doi:10.1056/NEJMoa1915928.
  3. Baral R, et al. Exercise training improves exercise capacity and quality of life in heart failure with preserved ejection fraction: A systematic review and meta-analysis of randomized controlled trials. European Heart Journal Open. 2024; doi:10.1093/ehjopen/oeae033.
  4. Bodea OM, et al. Effects of SGLT2 inhibitors on clinical outcomes, symptoms, functional capacity, and cardiac remodeling in heart failure: A comprehensive systematic review and multidomain meta-analysis of randomized trials. Journal of Clinical Medicine. 2026; doi:10.3390/jcm15010378.
  5. Bohula EA, et al. Palliative and end-of-life care during critical cardiovascular illness: A scientific statement from the American Heart Association. Circulation. 2025; doi:10.1161/CIR.0000000000001334.
  6. Brown TM, et al. Core components of cardiac rehabilitation programs: 2024 update: A scientific statement from the American Heart Association and the American Association of Cardiovascular and Pulmonary Rehabilitation. Circulation. 2024; doi:10.1161/CIR.0000000000001289.
  7. Chuzi S, et al. Integration of palliative care into heart failure care: Consensus-based recommendations from the Heart Failure Society of America. Journal of Cardiac Failure. 2025; doi:10.1016/j.cardfail.2024.10.435.
  8. Symptom relief for the dying patient. Merck Manual Professional Version. https://www.merckmanuals.com/professional/special-subjects/the-dying-patient/symptom-relief-for-the-dying-patient. Accessed Aug. 26, 2026.
  9. The dying patient. Merck Manual Professional Version. https://www.merckmanuals.com/professional/special-subjects/the-dying-patient/the-dying-patient. Accessed Aug. 26, 2026.
  10. Coiro S, et al. Short- and long-term mortality in patients hospitalized for dyspnoea with acute heart failure, respiratory infection, or both: Insights from the PARADISE cohort. European Journal of Heart Failure. 2026; doi:10.1093/ejhf/xuag160.
  11. De Oliveira MT Jr, et al. Heart failure management with β-blockers: Can we do better? Current Medical Research and Opinion. 2024; doi:10.1080/03007995.2024.2318002.
  12. Drazner MH, et al. 2024 ACC expert consensus decision pathway on strategies and criteria for the diagnosis and management of myocarditis. Journal of the American College of Cardiology. 2025; doi:10.1016/j.jacc.2024.10.080.
  13. Fan X, et al. Stroke related brain–heart crosstalk: Pathophysiology, clinical implications, and underlying mechanisms. Advanced Science. 2024; doi:10.1002/advs.202307698.
  14. Acute heart failure. Merck Manual Professional Version. https://www.merckmanuals.com/professional/cardiovascular-disorders/heart-failure/acute-heart-failure. Accessed Aug. 26, 2026.
  15. Chronic heart failure. Merck Manual Professional Version. https://www.merckmanuals.com/professional/cardiovascular-disorders/heart-failure/chronic-heart-failure. Accessed Aug. 26, 2026.
  16. Heart transplantation. Merck Manual Professional Version. https://www.merckmanuals.com/professional/cardiovascular-disorders/heart-failure/heart-transplantation. Accessed Aug. 26, 2026.
  17. Medications for heart failure. Merck Manual Professional Version. https://www.merckmanuals.com/professional/cardiovascular-disorders/heart-failure/medications-for-heart-failure. Accessed Aug. 26, 2026.
  18. Overview of heart failure. Merck Manual Professional Version. https://www.merckmanuals.com/professional/cardiovascular-disorders/heart-failure/overview-of-heart-failure. Accessed Aug. 26, 2026.
  19. Pulmonary edema. Merck Manual Professional Version. https://www.merckmanuals.com/professional/cardiovascular-disorders/heart-failure/pulmonary-edema. Accessed Aug. 26, 2026.
  20. Right heart failure and cor pulmonale. Merck Manual Professional Version. https://www.merckmanuals.com/professional/cardiovascular-disorders/heart-failure/right-heart-failure-and-cor-pulmonale. Accessed Aug. 26, 2026.
  21. Fonarow GC, et al. HF STATS 2025: Heart failure epidemiology and outcomes statistics — An updated 2025 report from the Heart Failure Society of America. Journal of Cardiac Failure. 2026; doi:10.1016/j.cardfail.2025.07.007.
  22. Garred CH, et al. Age-specific mortality trends in heart failure over 25 years: A retrospective Danish nationwide cohort study. The Lancet Healthy Longevity. 2024; doi:10.1016/S2666-7568(24)00029-1.
  23. Giannakoulas G, et al. Acute right ventricular failure: Pathophysiology, aetiology, assessment, and management. European Heart Journal. 2025; doi:10.1093/eurheartj/ehaf215.
  24. Graven LJ, et al. Palliative care and advanced cardiovascular disease in adults: Not just end-of-life care: A scientific statement from the American Heart Association. Circulation. 2025; doi:10.1161/CIR.0000000000001323.
  25. Heidenreich PA, et al. 2022 AHA/ACC/HFSA guideline for the management of heart failure: A report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines. Circulation. 2022; doi:10.1161/CIR.0000000000001063.
  26. Herrmann JJ, et al. Liberal fluid intake versus fluid restriction in chronic heart failure: A randomized clinical trial. Nature Medicine. 2025; doi:10.1038/s41591-025-03628-4.
  27. Hollenberg SM, et al. 2024 ACC expert consensus decision pathway on clinical assessment, management, and trajectory of patients hospitalized with heart failure focused update. Journal of the American College of Cardiology. 2024; doi:10.1016/j.jacc.2024.06.002.
  28. Irlik K, et al. Mortality and heart failure hospitalizations in heart failure with preserved ejection fraction compared to heart failure with reduced ejection fraction: A systematic review and meta-analysis. ESC Heart Failure. 2026; doi:10.1093/eschf/xvag026.
  29. Jones NR, et al. Survival of patients with chronic heart failure in the community: A systematic review and meta-analysis. European Journal of Heart Failure. 2019; doi:10.1002/ejhf.1594.
  30. Khan SS, et al. Risk-based primary prevention of heart failure: A scientific statement from the American Heart Association. Circulation. 2025; doi:10.1161/CIR.0000000000001307.
  31. Kittleson MM, et al. Management of heart failure with preserved ejection fraction: 2026 ACC expert consensus decision pathway. Journal of the American College of Cardiology. 2026; doi:10.1016/j.jacc.2026.06.018.
  32. Krishna BA, et al. Cardiovascular disease and COVID-19: A systematic review. International Journal of Cardiology Heart & Vasculature. 2024; doi:10.1016/j.ijcha.2024.101482.
  33. Maddox TM, et al. 2024 ACC expert consensus decision pathway for treatment of heart failure with reduced ejection fraction: A report of the American College of Cardiology Solution Set Oversight Committee. Journal of the American College of Cardiology. 2024; doi:10.1016/j.jacc.2023.12.024.
  34. Peled Y, et al. International Society for Heart and Lung Transplantation guidelines for the evaluation and care of cardiac transplant candidates — 2024. Journal of Heart and Lung Transplantation. 2024; doi:10.1016/j.healun.2024.05.010.
  35. Subramaniam A, et al. Advanced heart failure characteristics and outcomes in commercially insured U.S. adults. JACC: Heart Failure. 2023; doi:10.1016/j.jchf.2023.06.029.
  36. Tseng MCM, et al. Incidence and risk of cardiovascular outcomes in patients with anorexia nervosa. JAMA Network Open. 2024; doi:10.1001/jamanetworkopen.2024.51094.
  37. Walsh MN, et al. AHA/ACC/ESC/WHF expert consensus document: Second universal definition of heart failure (2026). Circulation. 2026; doi:10.1161/CIR.0000000000001455.