What Is Acute Heart Failure? Here’s What You Need to Know

We all think we understand what acute heart failure is, but the reality is complicated. This aggressive syndrome causes a lot of damage—here's what cardiologists need you to know.

If ever there were a prize awarded for “most misleading name given to a medical condition,” heart failure would win hands down.

“Heart failure (also called congestive heart failure) is a terrible name which suggests the heart has stopped working completely,” says Anthony Steimle, MD, a cardiologist and assistant physician in chief of cardiovascular services at Kaiser Permanente in Santa Clara, California. In fact, the heart has not stopped working. The heart muscle, however, is damaged.

Specifically, the heart can become weak and unable to pump blood (systolic heart failure), or the heart can become stiff and unable to fill with blood adequately (diastolic heart failure).

Some people may not even realize they have heart failure, blaming the subtle symptoms on aging or being out of shape. Yet, according to the Heart and Stroke Foundation, about 600,000 Canadians are living with heart failure.

Heart disease is the second leading cause of death in Canada. And yet, surprisingly, it is largely preventable.

Over time, however, unhealthy lifestyle choices and poorly controlled diseases such as diabetes contribute to heart failure. “Heart failure can be progressive, leading to persistent illness, becoming life-threatening, and sometimes requiring advanced therapies including heart transplantation or mechanical device support,” says Michele Hamilton, MD, director of the Heart Failure Program in the Smidt Heart Institute at Cedars-Sinai, in Los Angeles.

(Related: Is Heart Disease Genetic?)

What is acute heart failure?

“Acute” is used when the symptoms of heart failure are suddenly worse—as opposed to chronic symptoms—and necessitate unplanned doctor visits or hospitalization. Sometimes, acute heart failure is the first time a person is aware they have existing heart failure. “If someone has acute heart failure from a virus, heart rhythm problem, drugs, etc., it may resolve completely if the precipitating cause is removed or fixed and treatment is initiated quickly and sustained,” says Dr. Hamilton.

So when should you call your doctor or head to the emergency room? If the symptoms are mild, then it’s reasonable to see your primary care physician or cardiologist, says cardiologist Jeffrey Teuteberg,  section chief of heart failure, cardiac transplantation, and mechanical circulatory support at Stanford Health Care in Pittsburgh. On the other hand, if the symptoms are severe and sudden onset, such as feeling short of breath with minimal exertion or at rest, then seeking emergency care is prudent.

Symptoms of acute heart failure

There are many symptoms of acute heart failure. They may occur one after the other or all at once. The most common symptoms associated with acute heart failure are:

  • Shortness of breath while lying down or on exertion; or shortness of breath that wakes you up, gasping for air
  • Elevated blood pressure
  • Elevated heart rate, irregular heartbeat, or palpitations
  • Chest pain
  • Fatigue
  • Confusion
  • Dry cough that is often worse when lying flat
  • Abdominal bloating
  • Weight gain of two to three pounds in one day or five pounds in a week
  • Feeling full shortly after you start eating
  • Loss of appetite
  • Nausea
  • Dizziness
  • Low blood pressure
  • Swelling in the feet, ankles, and legs
  • Leg pain
  • Trouble sleeping
  • Cold feet and hands, fingers and toes

(Related: 6 Types of Heart Disease Doctors Need You to Know)

Risks for heart failure

Aging is the primary risk factor for heart failure. While you can’t stop aging, you do hold the power to lower and manage most of the other risks.

“It is important to recognize that for much of heart disease, prevention and the motivation to prevent heart disease is critical,” says Manesh Patel, MD, chief of the division of cardiology and co-director of the Duke Heart Center at Duke University School of Medicine in Durham, North Carolina. “For example, patients with hypertension or diabetes may not immediately feel bad. But control of hypertension and/or diabetes will prevent their heart from developing heart failure that is symptomatic and/or potentially worsening.”

Other risk factors for heart failure include:

  • High blood pressure
  • Fatty blockage in the arteries
  • Diabetes
  • Obesity
  • Sleep apnea
  • Heart attack
  • History of a heart murmur or damage to heart valves
  • Heart muscle disease and enlargement of the heart
  • Heart defects at birth
  • Family history of an enlarged heart
  • Lung disease

(Related: What Causes Heart Disease? 9 Things Doctors Need You to Know)

Types of heart failure

The onset of acute heart failure can manifest on the right, left, or both sides of your heart. Ventricles—the two large chambers where blood pumps out of the heart—can harden or stretch out and fail. This can lead to acute heart failure, such as:

Right-sided heart failure

Right-sided heart failure tends to occur at the same time as left-sided heart failure. This is because when the left side fails, this puts more pressure on the right side of the heart to pump blood, which can lead to damage and, essentially, heart failure. In these cases, patients can experience fluid buildup in the veins, which can lead to swelling in the legs and feet.

Left-sided heart failure

Left-sided heart failure occurs when the left ventricle doesn’t pump properly, causing blood to back up in your lungs. This can lead to shortness of breath. Here are the two main types:

Systolic heart failure

This occurs when the left ventricle is unable to contract normally. This means the heart is weakened or enlarged and is unable to sufficiently pump blood throughout the rest of the body.

Diastolic heart failure

This happens when there is not enough blood to fill the left ventricle. In other words, the heart is unable to pump sufficient blood to circulate throughout the body. This can cause the ventricle to stiffen.

Stages of heart failure

Identifying the stage of heart failure sets the course for treating and managing heart failure and acute heart failure. There are a couple of classification systems doctors use to determine which stage of heart failure is present. One is the New York Heart Association (NYHA) Functional Classification, which characterizes the patient’s symptoms while performing physical tasks. The NYHA has four stages:

  • Stage 1: Cardiac disease present with no symptoms. Ordinary physical activity is not limited.
  • Stage 2: Mild limitations of physical activity with symptoms of shortness of breath, fatigue, and palpitations.
  • Stage 3: Activity is significantly limited with shortness of breath, fatigue, and palpitations. Comfortable at rest.
  • Stage 4: Severe limitations with any physical activity. Symptoms of heart failure present during activity and at rest.

The other classification doctors use in conjunction with the NYHA is The American College of Cardiology (ACC) and the American Heart Association (AHA) classification system for heart failure. This system complements the NYHA. It also includes the patient who does not yet have heart failure, but is at high risk for developing heart failure.

  • Stage A: At risk for heart failure, but with no heart failure symptoms and absence of structural heart disease, an umbrella term that refers to defects in the heart from aging, injury, infection, or defect at birth.
  • Stage B: Structural heart disease with no symptoms or signs of heart failure.
  • Stage C: Structural heart disease with preceding or current symptoms of heart failure.
  • Stage D: Progression of heart failure despite following a medically directed care plan utilizing medicine, surgery, or device therapy.

(Related: 8 Causes of Exercise-Related Chest Pain Besides a Heart Attack)

Treatments for acute heart failure

Acute heart failure is a life-threatening condition. “When the pumping function of the heart becomes very poor, patients may have low blood pressure that requires support with medicines or devices,” says Dr. Teuteberg. “With very reduced heart function, other organs may suffer from poor blood flow such as the kidneys and liver. Patients may also experience abnormal heart rhythms that can result in palpitations, but when faster and longer-lasting, can result in fainting or even sudden death.”

If you have acute heart failure, you’ll be hospitalized and immediately assessed and stabilized for life-threatening complications such as respiratory failure. You may also be put on supplemental oxygen and medications to treat symptoms, but you won’t be discharged until you’re in stable condition.

“For acute heart failure, the most common approach focuses on investigating the cause of the heart dysfunction, giving diuretics (water pills) to get rid of extra fluid retention, and starting the patient on medications to protect their heart,” says Dr. Hamilton.

Treatment regimens that may begin in the hospital or after discharge could include a combination of medications, surgical procedures (such as valve repair or replacement, bypass, or pacemaker) to help your heart function, and implementing lifestyle changes such as following a heart-healthy diet and staying away from the foods cardiologists never eat.

(Related: 7 Supplements Heart Doctors Take Every Day)

Diagnosing acute heart failure

Depending on your condition, your doctor will order various imaging tests to help diagnose heart failure and the stage of heart failure. These tests take a closer look at the size of your heart, the chambers, valves, and arteries, the fluid around your heart, blood flow function, electrical activity, and how stress affects your heart. Some of them are non-invasive, like imaging, and others are invasive, such as cardiac catheterization.

Blood tests might be done to check for thyroid and kidney function, anemia, high cholesterol, sodium and potassium levels, and certain hormones found in some types of heart failure.

Here are some of the tests for your heart that are used to diagnose acute heart failure:

  • Chest x-ray
  • Electrocardiogram
  • Echocardiogram
  • Cardiac Catheterization
  • Ventriculography
  • MRI
  • PET scan
  • Multigated Acquisition Scan
  • Stress test

(Related: 7 Silent Signs of a Heart Attack)

Prognosis after acute heart failure

Acute heart failure might feel seem like a grim diagnosis, but that’s simply not the case, according to Dr. Steimle and Dr. Hamilton. “The prognosis is highly variable, and some people can live with even advanced heart failure for decades,” says Dr. Steimle.

Among the variables that affect prognosis: the multiple conditions that can cause heart failure. Some are more serious than others. For instance, kidney disease (often due to diabetes) is a common contributing factor to heart failure. It often makes treatment difficult because diuretics are used to reduce fluid retention in heart failure patients. Yet, the kidney’s response to hold onto fluids can intensify, reducing how well the kidneys filter blood and worsen kidney function.

“The kidneys rely on blood flow from the heart in order to filter blood,” explains Dr. Steimle. “The heart relies on the kidneys to excrete excess fluid. When the heart and kidneys are functioning abnormally, the problem is compounded.”

The other variables that impact prognosis: how well a patient responds to medication, devices, surgeries, and healthy lifestyle changes. “The best chance of recovery or stabilization is when the patient and family work closely with the medical team,” says Dr. Hamilton. This encompasses a combination of medical therapy, important lifestyle changes—including a low-salt diet, avoiding alcohol, cigarettes, and other recreational drugs, and initiating a walking program, Dr. Hamilton says.

Living with acute heart failure

While heart failure is a life-altering disease, it isn’t a death sentence. “Patients often read online that half of the people with heart failure die within five years of diagnosis,” says Dr. Steimle. “I point out the highly variable prognosis depending on the response to therapy and the causes of heart failure.”

Also, the typical heart failure patient is in their mid-70s, often has a heart condition, plus other serious conditions such as coronary artery disease, diabetes, and kidney problems, he adds. “If I told you this person had a 50 percent chance of living to at least 80 and some would live to be 90, is that a death sentence?”

What about that response to therapy Dr. Steimle mentioned? Therapy includes the things you can do outside the doctor’s office to take care of your heart. Be proactive and take your medications, watch your fluid and salt intake, make time for a daily walk, eat a heart-healthy diet, and closely monitor your weight, and you’ll be one step ahead of heart failure.

Next: Could Your Chest Tightness Be Due to Anxiety? Why It Happens