Heart Attack, Cardiac Arrest, Heart Failure—What's the Difference?

Heart attack, cardiac arrest and heart failure are not the same thing. They are three different problems with radically different causes and treatments.

However, each of these dangerous conditions can be caused by preventable factors such as high cholesterol, high blood pressure and diabetes, said Janet Wei, MD, co-director of the Stress Echocardiography Lab and the Erika J. Glazer Chair in Women's Cardiovascular Research, Education and Innovation at the Smidt Heart Institute at Cedars-Sinai.

“It’s important to know your numbers, which can guide your clinicians to help you lower your risk for heart disease,” she said.

Heart Attack

Most heart attacks are caused by a lack of blood flow to the heart because of a blood clot or a buildup of plaque in the arteries. However—especially in women—heart attacks can have other causes, such as a tightening of the arteries, called coronary spasm, or a tear of the arteries, called a coronary dissection.

Symptoms may start slowly and persist for hours, days or weeks before the heart attack. Not everyone has the same symptoms, but about two-thirds of people have chest pain or discomfort—such as tightness or heaviness—or shortness of breath, or they feel tired days or weeks before the heart attack.

A heart attack may cause pain in the middle of the chest that can spread to the back, jaw or arms. Sometimes people feel pain in their stomach and mistake the heart attack for indigestion.

Other symptoms may include shortness of breath, nausea, faintness or lightheadedness, sudden cold sweats, heavy pounding of the heart, abnormal heart rhythms, loss of consciousness and unusual fatigue.

“If you have any symptoms at all, it’s important to seek medical attention to be evaluated and potentially prevent a heart attack,” Wei said.

If you believe someone is experiencing the symptoms of a heart attack, call 911 immediately.

High blood pressure, high cholesterol, smoking and a family history of an early heart attack or blocked arteries put people at risk for a heart attack.

“Family history is particularly important and changes the way doctors think about your symptoms,” Wei said. “We don't often ask our family for their cardiac history, but this information can help us identify our risk factors earlier.”

Cardiac Arrest

Cardiac arrest is when the heart stops beating and needs to be restarted.

While a heart attack is a circulation problem, cardiac arrest is an electrical problem triggered by a disruption of the heart’s rhythm. Most heart attacks do not lead to cardiac arrest. However, when cardiac arrest happens, a heart attack is a common cause.

Cardiac arrest is a medical emergency that is not necessarily preceded by heart disease. But many patients experience warning symptoms up to a month before cardiac arrest. Cedars-Sinai research has uncovered differences in these early symptoms based on patients’ sex: Women are most likely to experience shortness of breath, while men usually feel chest pain.

Because cardiac arrest stops the heart from beating, the brain, lungs and other organs do not get the blood and oxygen they need. Cardiac arrest can lead to death within minutes if not treated.

During cardiac arrest, a person will likely experience dizziness, shortness of breath and loss of consciousness. Within seconds of cardiac arrest, a person will become unresponsive and have trouble breathing.

Call 911 immediately if you think someone has gone into cardiac arrest.

When bystanders take action and immediately perform CPR and use an automated external defibrillator (AED), it can triple the chances a person will survive cardiac arrest. CPR is intended to pump the heart to get blood flowing and circulating to the brain and other organs. The AED sends an electric shock to the heart in an attempt to restore its normal rhythm.

Nine out of 10 cardiac arrest victims who receive a shock in the first minute will survive, but women, children, and Black and Hispanic people receive less bystander assistance, Wei said.

Learning how to perform CPR and use an AED properly, on anyone, takes just a few short hours and can help save a life. The American Red Cross and American Heart Association have extensive programs on learning how to perform CPR and use an AED.

Heart Failure

Heart failure occurs when the heart muscle fails to pump as much blood as the body needs. It is usually a long-term, chronic condition, but it may come on suddenly. Systolic heart failure (heart failure with reduced ejection fraction) is caused by a weakened heart muscle, while diastolic heart failure (heart failure with preserved ejection fraction) is characterized by a stiffness of the heart muscle.

In heart failure, the hormone and nervous systems attempt to compensate for the lack of blood. The body may raise blood pressure, making the heart beat faster and causing it to hold on to salt and water. If this retained fluid builds up, the condition is called congestive heart failure.

In the early stages of congestive heart failure, there may be no symptoms. When symptoms do develop, they may include weight gain, nausea and others not normally associated with the heart, such as:

• Dry, hacking cough, especially when lying down

• Confusion, sleepiness and disorientation in older people

• Dizziness, fainting, fatigue or weakness

• Fluid buildup, usually in the legs, ankles and feet

• Increased urination at night

• Nausea, abdominal swelling, tenderness or pain that may result from fluid in the body and backup of blood in the liver

• Rapid breathing

• Bluish skin

• Feelings of anxiety, restlessness and suffocation

• Shortness of breath and lung congestion

• Wheezing and spasms in the airway, similar to asthma

Heart failure is usually the result of another disease, most commonly coronary artery disease and high blood pressure. Diabetes, obesity and substance abuse are also major risk factors for developing heart failure. Counseling and support groups can help people experiencing addiction to alcohol, cigarettes and amphetamines, Wei said.

Heart failure can affect people of any age, especially if they were born with a heart defect or other genetic factors. While the condition most often affects older people whose hearts may be weakened by age-related conditions, heart failure is increasingly affecting younger people.

Heart failure can be managed with medications, surgery, implantable devices and lifestyle changes.

Talk to a doctor if you are concerned about your heart health or if you have a family history of heart attack, heart failure or cardiac arrest. Clinicians work with each patient to develop the best approach to prevent or treat heart disease.