Heart Failure: What It Means, What to Watch For, and How It Is Treated

Hearing the words “heart failure” can feel frightening. It sounds like the heart has stopped working, but that is not what it means. In most cases, heart failure means the heart is not pumping blood as well as it should or not filling properly before it pumps.

This matters because your body depends on a steady flow of blood to carry oxygen and nutrients where they are needed. When the heart cannot keep up, symptoms like shortness of breath, swelling, and tiredness can start to affect daily life.

The good news is that heart failure can often be managed. With the right treatment, healthy habits, and regular follow-up, many people live with it for years.

What is heart failure?

Heart failure is a condition in which the heart has trouble doing one or both of these jobs:

• Filling with blood

• Pumping blood out to the body

This can happen because of a problem with the heart’s structure or how it works.

You may also hear the term congestive heart failure. This is used when heart failure causes fluid buildup, such as swelling in the legs or congestion in the lungs. But not everyone with heart failure has obvious fluid buildup, so “heart failure” is the better overall term.

Why does heart failure happen?

The three main causes are:

• Coronary artery disease, which affects blood flow to the heart muscle

• High blood pressure

• Diabetes

Heart failure becomes more common with age. In many people, more than one risk factor is involved.

Other causes can include:

• Heart valve problems

• Abnormal heart rhythms

• Heart muscle disease

• Kidney disease

• Obesity

• Thyroid problems

• Lung disease

• Alcohol, tobacco, or stimulant drugs

• Certain chemotherapy treatments

• Some inherited or autoimmune conditions

How does heart failure affect the body?

When the heart cannot pump effectively, two big problems can happen.

1. Not enough blood reaches the body

This can lead to:

• Fatigue

• Weakness

• Cool or pale legs

• Kidney problems

• Low blood pressure in severe cases

2. Fluid backs up

This can cause:

• Fluid in the lungs, leading to shortness of breath

• Swelling in the legs, ankles, or feet

• Fullness in the belly

• Liver congestion

• Needing to urinate more often at night

Common symptoms to look out for

Heart failure symptoms can come on slowly or get worse suddenly.

Common symptoms include:

• Shortness of breath

• Swelling in the legs or feet

• Feeling tired or weak

• Needing extra pillows to sleep comfortably

• Waking up at night short of breath

• Coughing, especially at night

• Fast heartbeat or irregular heartbeat

• Less ability to exercise or do normal activities

• Loss of appetite or nausea in some people

Symptoms linked more to the left side of the heart

The left side of the heart pumps blood to the body. When it struggles, fluid can back up into the lungs.

This can cause:

• Shortness of breath

• Trouble breathing when lying flat

• Nighttime episodes of breathlessness

• Coughing or wheezing

Symptoms linked more to the right side of the heart

The right side of the heart helps move blood to the lungs. When it struggles, fluid can build up in the body.

This can cause:

• Swelling in the legs

• Swelling in the neck veins

• Belly discomfort

• Enlarged liver or spleen

• Fluid in the abdomen

Different types of heart failure

Heart failure is not the same in every person.

Heart failure with reduced ejection fraction

• This means the heart’s pumping strength is reduced. The term ejection fraction refers to how much blood the heart pushes out with each beat.

Heart failure with preserved ejection fraction

• This means the heart may still squeeze fairly well, but it has become stiff and does not fill properly.

Heart failure with mildly reduced ejection fraction

• This falls in between the two groups above.

Heart failure with improved ejection fraction

• This describes people whose heart function was reduced before but later improved.

Doctors also classify heart failure by:

• Stage, from being at risk to having advanced disease

• Symptom level, meaning how much it affects daily activity

These classifications help guide treatment.

How doctors diagnose heart failure

Heart failure is diagnosed using symptoms, an exam, and tests.

The first tests often include:

Blood tests for natriuretic peptides

These include BNP or NT-proBNP. These substances are released when the heart is under strain. Higher levels can support the diagnosis, though results must always be looked at along with the full clinical picture.

Echocardiogram

This is an ultrasound of the heart. It is one of the most important tests because it shows:

• How well the heart pumps

• Heart size

• Heart thickness

• Valve problems

• Other structural changes

Chest x-ray

This can show:

• Heart enlargement

• Fluid in the lungs

• Other chest problems that may explain symptoms

ECG

This checks the heart’s electrical activity and can help find:

• Abnormal rhythms

• Signs of strain

• Evidence of heart damage or other heart conditions

Doctors may also order other blood tests to look for causes and related problems, such as:

• Anemia

• Diabetes

• Kidney problems

• Thyroid disease

• Iron deficiency

• Liver congestion

What can make heart failure worse?

Heart failure can get worse over time or suddenly flare up. This is sometimes called acute decompensated heart failure, which means symptoms have suddenly become worse.

Possible triggers include:

• Infection

• Heart attack

• Not taking medicines as prescribed

• Too much salt in the diet

• Certain medicines that can worsen heart failure

• Worsening kidney function

• Uncontrolled blood pressure

• New heart rhythm problems

Treatment: what helps?

Treatment usually involves a mix of lifestyle changes, careful monitoring, and medicines. In more advanced cases, devices or surgery may be needed.

Healthy habits that matter

These steps are an important part of care:

• Regular aerobic activity, such as brisk walking

• Weight management

• Healthy eating patterns, such as DASH-style or Mediterranean-style eating

• Avoiding too much salt

• Stopping smoking

• Avoiding alcohol and recreational drugs

Daily self-checks at home

People with heart failure are often advised to keep track of:

• Daily weight

• Blood pressure

• Breathing

• Swelling

• Medicine side effects

  
  

A quick weight gain can be a warning sign. A change of more than 2 kg in 3 days should prompt medical advice.

Medicines used for heart failure

Medicines are chosen based on the type of heart failure and the person’s overall health.

Common treatment groups include:

• Diuretics, which help remove extra fluid

• Beta blockers, which reduce the heart’s workload

• RAAS blockers, which help relax blood vessels and reduce strain on the heart

• SGLT2 inhibitors

• Mineralocorticoid receptor antagonists

For some people, other medicines may be added if symptoms continue.

For heart failure with reduced ejection fraction

• Treatment usually includes a combination of medicines that improve symptoms and can also help people live longer and stay out of the hospital.

For heart failure with preserved ejection fraction

Treatment often includes:

• SGLT2 inhibitors for all patients

• Diuretics if there is fluid buildup

• In some cases, an MRA, ARNI, or ARB

Treating related health problems is also important

Most people with heart failure have other medical conditions too. Managing those problems can make a real difference.

Important examples include:

• High blood pressure

• Diabetes

• Iron deficiency

• Obesity

• Sleep apnea

Medicines that may worsen heart failure

Some drugs can make heart failure worse or lead to fluid retention. Examples include:

• NSAID pain relievers

• Some calcium channel blockers

• Pioglitazone

• Some diabetes medicines in the DPP-4 inhibitor group

• Some antiarrhythmic drugs

This is one reason it is so important to check with a healthcare professional before starting new medicines, even over-the-counter ones.

When advanced treatment is needed

Some people develop advanced heart failure, which means symptoms continue to seriously affect daily life even with treatment.

Options may include:

• Implantable devices to prevent dangerous heart rhythms

• Cardiac resynchronization therapy, which helps the heart beat in a more coordinated way

• Mechanical circulatory support, such as heart pump devices

• Heart transplant

A heart transplant is the only true cure for advanced heart failure, but it is only suitable for some patients.

Possible complications

Heart failure can lead to serious complications, including:

• Sudden worsening of symptoms

• Kidney problems

• Abnormal heart rhythms

• Cardiogenic shock

• Stroke

• Chronic kidney disease

• Liver damage from long-term congestion

• Leg ulcers from poor circulation and swelling

What is the outlook?

The outlook depends on many things, including:

• The type and severity of heart failure

• Other health conditions

• How well treatment is followed

• Whether symptoms and fluid buildup improve

Some signs linked with a worse outlook include:

• Ongoing swelling or congestion

• Low blood pressure

• Low sodium levels

• High BNP or NT-proBNP levels

• Diabetes, anemia, or obesity

• Unplanned weight loss

Even so, outlook can vary a lot from person to person. Many people do better when treatment is started early and followed closely.

When to seek medical help

A person with heart failure should get medical advice if they notice:

• More shortness of breath

• Increasing swelling

• Rapid weight gain

• New dizziness

• Trouble doing usual activities

• Worsening cough, especially at night

Urgent care is especially important if there is severe breathing trouble, chest pain, confusion, or signs of very low blood flow.

Key takeaways

• Heart failure does not mean the heart has stopped. It means the heart is not working as well as it should.

  
  

• The most common causes are:

• Coronary artery disease

• High blood pressure

• Diabetes

  
  

• The most common symptoms are:

• Shortness of breath

• Swelling in the legs or feet

• Fatigue

  
  

• Diagnosis usually includes:

• BNP or NT-proBNP blood tests

• Echocardiogram

• Chest x-ray

• ECG

  
  

• Treatment often includes:

• Healthy lifestyle changes

• Careful self-monitoring

• Medicines

• Treatment of related health conditions

• In some cases, devices or transplant evaluation

Most importantly, heart failure is a condition that can be managed. Knowing the symptoms, getting checked early, and sticking with treatment can make a big difference.