Heart Failure

(Congestive Heart Failure)

Reviewed/Revised Dec 2022
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What is heart failure?

Your heart pumps blood to carry oxygen and nutrients to the rest of your body. Heart failure is when your heart doesn’t pump blood as well as it should. It doesn’t mean your heart has stopped (that's called cardiac arrest).

  • If you have heart failure, your heart pumps less blood

  • That causes fluid to back up in your lungs and other body parts

  • Extra fluid in your lungs makes it hard to breathe

  • Extra fluid in your legs makes them swell

  • If your kidneys don’t get enough blood, they make less urine so the body has more fluid

  • That extra fluid makes your heart work even harder

  • Then, your heart failure can get even worse

The extra fluid in your body is called “congestion.” That’s why heart failure is sometimes called “congestive heart failure.”

Who can have heart failure?

Anyone can have heart failure, even young children (especially children born with a heart defect). However, it’s much more common in older people, because:

  • Older people are more likely to have other heart problems that can cause heart failure

  • Older people are more likely to have high blood pressure and diabetes, which can lead to heart failure

  • The heart's walls stiffen with age

What causes heart failure?

Any problem that makes your heart weak or stiff can cause heart failure. Common examples of such problems are:

Other problems that can cause heart failure are an irregular heart rhythm, low number of red blood cells (anemia), thyroid gland problems, and heart muscle infections.

Most disorders cause heart failure only after many years. However, some disorders, such as a major heart attack, can cause heart failure quickly.

Often, a person’s heart failure has more than one cause.

What are the symptoms of heart failure?

  • Feeling like you can’t catch your breath, which worsens when you lie flat

  • Feeling tired all over

  • Swelling in your feet, ankles, and legs

Symptoms usually develop slowly. At first you may feel out of breath only when you climb stairs and notice only a little leg swelling at the end of the day. Later, you may feel out of breath or tired when you do ordinary activities. When heart failure is severe, you may be out of breath even sitting in a chair and have a lot of leg swelling all the time.

Heart failure can shorten your life, especially when it's severe. Treatment can help you live longer.

How can doctors tell if I have heart failure?

Doctors first suspect heart failure based on your symptoms. To make sure they’re right, they’ll do a physical exam, a chest x-ray, and tests to tell how well your heart is working. Common heart function tests are:

  • Electrocardiography (ECG/EKG): A quick, painless, and harmless test that measures your heart’s electrical function

  • Echocardiography (also called an echo): A type of ultrasound that uses sound waves to create a video that shows how well your heart is pumping and how well your heart’s valves are working

Can my doctor treat my heart failure?

Yes. Although you may have to live with heart failure for the rest of your life, treatment can improve and prolong your life. Treatment usually involves treating the disorder that's causing your heart failure, taking medicines, and making changes to your lifestyle.

What types of medicines can treat heart failure?

Many different types of medicines help treat heart failure. Some of the more common types are:

  • ACE inhibitors: Widen your blood vessels to lower blood pressure so your heart doesn't have to work as hard, and help your kidneys get rid of extra water

  • Beta-blockers: Slow your heart rate so your heart doesn't have to work as hard, and can help a stiff heart relax so it fills with blood better

  • Diuretics (water pills): Help your kidneys get rid of the extra water by making you urinate more

If you have very bad heart failure that isn’t responding to medicines, doctors may suggest a heart transplant or a mechanical device that helps pump blood.

What can I do if I have heart failure?

Try to be more comfortable

  • Raise up your legs when sitting down

  • Sleep with several pillows under your head to make it easier to breathe

Manage your medicines

  • Remember to take your medicines

  • Always check with your doctor before taking any new medicine, even those you buy over-the-counter at the drug store

Keep in touch with your doctor or health care team

  • Weigh yourself every day (use the same scale at the same time of day while wearing a similar amount of clothing) and write down your weight so you know if you're retaining too much fluid

  • Pay attention to your symptoms each day

  • If your weight increases by more than a few pounds or your symptoms start to get worse, let your health care team know

Have a healthy lifestyle

  • Cut down on salt by not eating salty foods and snacks and not adding salt to food on your plate or when cooking

  • Stay as active as you can, even if you can’t work up a sweat

  • Lose weight, if you're overweight

  • Stop smoking and stop drinking alcohol

  • Get a flu shot each year

How can I prevent heart failure?

Follow your doctor's advice on treating health problems that can cause heart failure before they lead to heart failure.

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