Acute heart failure

Heart failure occurs when your heart can’t pump enough blood to meet your body’s demand. This can be chronic, meaning it happens slowly over time. Or it can be acute, meaning it happens suddenly.

According to a 2014 study, approximately 26 million people worldwide were living with heart failure at the time. In the United States, heart failure is a major cause of people over 65 being admitted to the hospital. This may be because people are living longer with heart disease, which can lead to heart failure over time.

Shortness of breath is the most common symptom of acute heart failure. From there, the condition shares many of the same symptoms as chronic or severe heart failure.

These symptoms may be much more pronounced with acute heart failure though. Your legs and abdomen may suddenly swell, and you could rapidly gain weight from retaining fluid. This could mean 2 to 3 pounds in a 24-hour period, or 5 pounds over the course of a week. You may also feel nauseous or lose your appetite.

Other symptoms of both acute and chronic heart failure include:

If not treated, heart failure can lead to a heart attack. A heart attack is typically caused by a blockage in an artery. The blockage prevents oxygen from reaching the heart, leading it to pump erratically or not at all. If you’re having a heart attack, you may also have chest pain. Learn more about the warning signs of a heart attack.

Older adults may have several health conditions. This can make it difficult to isolate symptoms of a heart problem from those caused by other conditions.

If you’re experiencing any of these symptoms and are unsure why, seek emergency medical treatment.

According to a 2008 study, people hospitalized with acute heart failure had an average delay time of 13.3 hours between noticing symptoms and getting treatment. The faster that you identify your symptoms and seek medical attention, the better your outlook.

Acute or chronic failure can begin on either the left or right side of your heart, or both sides may fail at the same time. The chambers where your blood is pumped out of the heart are called ventricles. These may stiffen so that they no longer fill properly. Or, if your heart muscle is too weak, the ventricles can stretch out and fail to work efficiently.

These are a few types of heart failure:

Left-sided heart failure

This occurs when your left ventricle isn’t pumping efficiently. Instead of pumping blood out to your body, the blood backs up into your lungs. You may become short of breath as a result.

There are two types of left-sided heart failure:

Systolic heart failure is the most common cause of heart failure. It happens when your heart is weak or enlarged. During systolic heart failure, the muscle in your left ventricle is unable to contract or shorten. This prevents blood from being pumped effectively out to your body.

Diastolic heart failure happens when blood isn’t able to properly fill your left ventricle. Because of this, your heart pumps less blood to your body than normal. This low blood flow is likely caused by the ventricle stiffening.

Symptoms of diastolic heart failure are indistinguishable from those of systolic heart failure. Because of this, diagnosis can only be performed using Doppler echocardiography.

Right-sided heart failure

This usually happens simultaneously with left-sided heart failure. Failure of your left ventricle results in increased pressure and subsequent damage to the right side of your heart. This can prohibit the right side of your heart from pumping efficiently.

If the right side of your heart is unable to pump correctly, fluid can accumulate in your veins. This may cause your legs and feet to swell.

Learn more about how your heart works.

Although you may seem healthy, it’s possible to experience a sudden heart event that results in failure.

Causes of acute heart failure include:

Having one risk factor may be enough to trigger heart failure, and having a combination of risk factors increases that risk.

Risk factors include:

Many conditions weaken or damage the heart over time. This can lead to chronic heart failure. Some result from internal factors, such as disease or a birth defect. Others come from external factors, such as a poor diet and lack of exercise.

Conditions leading to chronic heart failure include:

  • high blood pressure
  • diabetes
  • faulty heart valves
  • coronary artery disease
  • inherited heart defects
  • damaged or inflamed heart

With all these conditions, the heart adapts over time until it just can’t adapt anymore. Then it fails. Sometimes one of these chronic conditions leads to an acute event.

To diagnose acute heart failure, your doctor will run certain tests. Your doctor can then classify the severity of your condition using a symptom- or stage-based scale to find the right treatment.

Tests for acute heart failure

Your doctor will assess your medical history and perform a physical exam. They’ll listen to your heart and lungs with a stethoscope to detect any congestion or abnormal heart rhythms. Your doctor may also check for fluid buildup in your abdomen, legs, and the veins in your neck.

In addition, your doctor might order some combination of the following tests:

  • Chest X-ray. This imaging test allows your doctor to better examine your heart and lungs.
  • Blood tests. These check your thyroid and kidney function.
  • Stress test. This type of test measures your heart activity during physical exercise.
  • Electrocardiogram. During this test, your doctor will attach electrodes to your skin and record your heart’s electrical activity.
  • Echocardiogram. This test uses sound waves to form an image of your heart that shows how much blood your heart is pumping.
  • Angiogram. During this test, your doctor will insert a thin tube into your groin or arm and into your coronary arteries. After injecting dye through a catheter, your doctor can see an image of your arteries.
  • CT scan. This test helps diagnose heart problems by showing your doctor detailed images of your organs. It involves lying inside a machine while the images are taken using X-rays.
  • MRI scan. This scan produces detailed images of your organs using magnets and radio waves instead of X-rays. Learn more about heart MRIs.

Classes and stages of heart failure

If you’re diagnosed with heart failure, your doctor may categorize the severity of your condition on one of two scales. This classification can help guide your treatment and recovery.

The New York Heart Association classification is a symptom-based scale. It classifies heart failure in one of four categories:

  • Class 1. You don’t experience any symptoms at any time.
  • Class 2. You can perform daily activities with ease, but feel fatigued or winded when you exert yourself.
  • Class 3. You have difficulty completing daily activities.
  • Class 4. You feel short of breath even when you’re at rest.

The American College of Cardiology/American Heart Association classification is a stage-based system. It’s used to classify your risk for or level of heart failure. The letters A to D convey the stage that you’re in:

  • Stage A. You have one or more risk factors for heart failure, but you aren’t experiencing any symptoms.
  • Stage B. You have heart disease, but you don’t have any signs or symptoms of heart failure.
  • Stage C. You have heart disease, and you’re experiencing signs or symptoms of heart failure.
  • Stage D. You have advanced heart failure that requires specialized treatments.

Doctors often use these two classification systems together to determine the best treatment or prevention plan for you.

If you experience acute heart failure, you’ll be hospitalized until you’re in stable condition. During this time, you may be put on oxygen. You might also need supplemental oxygen in the long term.

Acute heart failure can have lasting effects on your body. Because of this, treatment is centered on managing symptoms and preventing future heart failure.

In some cases, acute heart failure can be caused by undiagnosed chronic heart failure. The cause of your acute heart failure will determine your treatment plan. Treatment for acute heart failure and chronic heart failure is often the same.

Treatment typically includes a combination of medication, surgery, and medical devices.


In many cases, a combination of at least two medications is necessary to manage heart trouble.

Some of these medications include:

  • Angiotensin-converting enzyme (ACE) inhibitors. This type of drug widens your blood vessels, which lowers blood pressure and increases blood flow. This makes your heart’s job easier.
  • Angiotensin II receptor blockers. These drugs are similar to ACE inhibitors, but some people have fewer side effects from this type of drug.
  • Beta-blockers. These drugs reduce blood pressure and slow your heart rate. They help to normalize the rhythms of your heart.
  • Digoxin (Lanoxin). This drug strengthens the contractions of your heart and makes it beat more slowly.
  • Diuretics. Also known as water pills, these medications prevent fluid from accumulating in your body.
  • Aldosterone antagonists. This is a kind of diuretic that may lengthen the lives of people with severe heart failure.

You may also need medicines to lower your cholesterol or treat chest pain. Your doctor may prescribe a blood thinner to avoid blood clots.

Depending on the cause of your heart failure, your doctor may also prescribe an antibiotic to treat infection.

Surgery and medical devices

Surgery is also widely used to treat heart failure. Some common types of heart surgery include:

Heart valve replacement or repair. If your heart fails because of a problematic heart valve, your doctor may want that valve repaired or replaced. This involves either repairing your own valve or implanting an artificial valve.

Coronary bypass surgery. In this surgery, your surgeon will remove a blood vessel from another part of your body. This blood vessel is fashioned into a new pathway to work around a clogged artery.

Your doctor may use one of the following devices to help restore function:

  • Biventricular pacemaker. This device helps the ventricles pump more efficiently by sending electrical impulses.
  • Implantable cardioverter-defibrillators (ICDs). ICDs are implanted under your skin, like a pacemaker. Wires tunnel through your veins to monitor your heart rhythm. If the rhythm deviates dangerously, the ICD tries to shock it back to normal.
  • Heart pumps. These mechanical devices can be used to keep people alive while they wait for a donor heart. Sometimes they are used instead of a transplant. This device can extend the lives of people who aren’t eligible for transplant surgery.

If your condition is severe, your doctor may recommend a heart transplant. This is typically a last resort and only explored if other treatments aren’t working. The demand for donor hearts is usually far greater than the supply.

Changing certain behaviors can reduce your heart failure symptoms. This may also lessen your risk for future instances of heart failure.

If you smoke, ask your doctor for help quitting. Smoking increases your heartbeat, decreases the amount of oxygen in your blood, and elevates your blood pressure. If you smoke, you won’t be considered for a heart transplant.

Your outlook depends on your overall health, as well as the cause and degree of your heart failure. Many people are able to manage their symptoms with heart medications or implanted medical devices.

Your outlook may be further complicated if your heart failure leads to kidney or liver damage or problems with your heart valves. Blood clots are also common after heart failure.

Work with your doctor to determine your risk for these complications. They can devise a treatment plan that both alleviates your symptoms and reduces your risk for future incidents. Learn about L-arginine and its benefits for the heart.

Some risk factors, such as genetics or chronic illness, can’t be avoided. The key to preventing heart failure is to reduce the risk factors that you can control.

Many of the lifestyle changes recommended for heart failure recovery can also reduce or eliminate conditions that lead to heart failure. These conditions include high blood pressure and high cholesterol.

If you’re at risk for heart failure, you should consider these lifestyle changes:

  • maintaining a healthy weight
  • getting regular exercise
  • eating a balanced, healthy diet
  • quitting smoking
  • finding ways to manage stress
  • managing preexisting conditions, especially heart conditions

Be sure to have regular checkups and report any unusual symptoms to your doctor. Find out your risk factors through the American Heart Association’s heart disease risk calculator.