What Is Heart Failure?

Reviewed by Brunilda Nazario, MD on June 08, 2021

The name of this condition can be a little confusing. When you have heart failure, it doesn't mean your ticker stopped beating. What's really going on is that your heart can't pump blood as well as a healthy one.

The chambers of your heart may respond by stretching to carry more blood to pump through your body. They may become stiffer and thicker. This helps keep blood moving for a while, but in time, your heart muscle walls may get weaker.

Your kidneys react by causing your body to hold on to water and salt. Fluid may start to build up in your arms, legs, ankles, feet, lungs, or other organs.

The American Heart Association and American College of Cardiology have defined four stages of heart failure to help people understand how the condition changes over time and the kinds of treatments that are used for each.

What Causes It?

Heart failure can be brought on by many conditions that damage the heart.

Coronary artery disease is a problem with the arteries that supply blood and oxygen to your heart. It means less blood flows to your heart muscle. When the arteries narrow or get blocked, your heart becomes starved for oxygen and nutrients and can't pump as well.


Heart attack may happen when a coronary artery is blocked suddenly, which stops the flow of blood to your heart muscle.

Cardiomyopathy is damage to your heart muscle. It can be caused by artery or blood flow problems, infections, and alcohol and drug abuse. Other diseases or genetic issues can also bring it on. Make sure your doctor knows your family's health history.

Conditions that overwork the heart include things like high blood pressure, heart valve disease, thyroid disease, kidney disease, diabetes, or heart defects you've had since you were born.

Types of Heart Failure

Systolic heart failure happens when your heart muscle doesn't squeeze with enough force. When that's the case, it pumps less oxygen-rich blood through your body.

With diastolic heart failure, your heart squeezes normally, but the ventricle -- the main pumping chamber -- doesn't relax properly. Less blood can enter your heart, and the blood pressure in your lungs goes up. When that happens, you get fluid in your lungs, legs, and belly.

Stage A

This is the period when you're more likely to get heart failure. You may be in this stage if you have:

Your chances are also greater when you have a history of:

An Inside Look at Heart FailureWhat does it mean to have a weak ticker, and how does it affect the whole body?77

SPEAKER: In a healthy heart,

blood from the body

is pumped through the right side

of the heart to the lungs

to pick up oxygen. From there,

the oxygen rich blood returns

to the left side of the heart,

which pumps it through the aorta

to the rest of the body.

Heart failure occurs when

the heart is unable to pump

enough blood to meet the body's


Conditions that damage

or overwork the heart muscle

can lead to heart failure

like high blood pressure,

coronary artery disease,

and diabetes.

Over time, the heart weakens

and either can't fill

with enough blood

or can't pump blood to the body

with enough force.

Sometimes both problems happen


To compensate, the heart

may beat faster.

And the chambers

may either stretch to hold more


or become

stiff and thickened to help pump

more blood through.

But this only makes the heart


Blood and fluid can back up

into the lungs.

And the kidneys may respond

by retaining water and salt.

This excess fluid causes

swelling in the body,

adding even more strain

on the heart.

While there is no cure for heart

failure, early diagnosis

and treatment can help people

who have it live longer, more

active lives.

Pixeldust Studios<br><br>National Heart, Lung, and Blood Institute: "What Is Heart Failure?"<br><br>Mayo Clinic: "Heart Failure."<br><br>MedlinePlus: "Heart Failure."<br><br>PubMed Health: "Heart Failure."/delivery/8f/4f/8f4fa394-5914-410a-8bf7-6352106ec7ab/vd-1714-heart-failure-animation_,4500k,1000k,2500k,750k,400k,.mp411/23/2016 00:00:00650350heart failure animation/webmd/consumer_assets/site_images/article_thumbnails/video/heart_failure_animation_video/650x350_heart_failure_animation_video.jpg091e9c5e81543718

Your doctor will probably recommend regular exercise and that you stop drinking alcohol, smoking, and using illegal drugs. You'll want to take steps to lower high blood pressure or high cholesterol.

If you have high blood pressure or had a heart attack, your doctor may prescribe beta-blockers.

When you have diabetes, high blood pressure, or other heart and blood vessel conditions like coronary artery disease, you may need to take an ACE inhibitor or an angiotensin II receptor blocker (ARB).

Stage B

You're in this phase if you never had symptoms of heart failure but you're diagnosed with systolic left ventricular dysfunction, which means the left chamber of your heart doesn't pump well. You may be in this group if you had or have:

  • Heart attack
  • Valve disease
  • Cardiomyopathy


Treatment will depend on your situation. Your doctor may suggest an ACE inhibitor or angiotensin II receptor blocker (ARB), or beta-blockers after a heart attack. They may add an aldosterone inhibitor if your symptoms continue while you're taking beta-blockers and ACE/ARB medications.

Surgery can repair coronary arteries and valves, or valves which may need to be replaced. Sometimes an implantable cardiac defibrillator (ICD) will help.

Stage C

You're in this phase if you have systolic heart failure along with symptoms such as:

  • Shortness of breath
  • Fatigue
  • Less ability to exercise

Your doctor may prescribe:

  • ACE inhibitors and beta-blockers
  • Angiotensin receptor blocker and neprilysin inhibitors

If your symptoms don't go away, you may need to take:

  • Hydralazine/nitrate combination
  • Diuretics (water pills) and digoxin
  • Aldosterone inhibitor, when your symptoms stay severe with other treatments
  • Soluble Guanylate Cyclase (sGC) stimulators

Devices such as a biventricular pacemaker or implantable cardiac defibrillator (ICD) may help.

You may need to change some things about your day-to-day life, too:

  • Eat less salt.
  • Lose weight if you're overweight.
  • Drink fewer fluids if necessary.
  • Stop drugs that make your condition worse.

Stage D

You're in this phase if you have systolic heart failure and advanced symptoms after you get medical care.

Some of the treatments from stages A, B, and C will help stage D, too. Your doctor may also discuss:

  • Heart transplant
  • Ventricular assist devices
  • Surgery options
  • Continuous infusion of intravenous inotropic drugs
WebMD Medical Reference



Cleveland Clinic Heart and Vascular Institute.

American College of Cardiology.

American Heart Association.

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