Centers of Excellence

Heart & Vascular Center

What is atrial fibrillation (A-fib)?

Atrial fibrillation (A-fib) is a type of arrhythmia (abnormal heartbeat) that affects almost five million Americans. It often originates in the left atrium (the upper left chamber of the heart). When atrial fibrillation occurs, the upper heart chambers beat in an unorganized rhythm. An A-fib heart rate is usually rapid, resulting in 100-200 beats per minute rather than the normal range of 60-100 beats per minute. If left untreated, A-fib can lead to chronic fatigue, congestive heart failure or stroke.

Types of Atrial Fibrillation

The types of A-fib include:

  • Occasional (paroxysmal): A-fib symptoms come and go, lasting for minutes or hours across multiple days. Symptoms typically end on their own in less than a week, but treatment may be required
  • Persistent: A-fib symptoms come and go, lasting longer than a week and requiring treatment to return the heart to a normal rhythm
  • Long-standing or continuous: Symptoms last longer than 12 months and require treatment to return the heart to a normal rhythm
  • Permanent: An irregular heart rhythm that is unable to return to a normal state and requires treatment to limit symptoms and complications

Risk Factors for Atrial Fibrillation

The risk factors for A-fib can vary from family history to other medical conditions to lifestyle choices. Managing controllable risk factors can reduce the chance of developing A-fib.

Key risk factors of A-fib include:

  • Heart disease
  • High blood pressure
  • Chronic health conditions, such as diabetes, kidney disease, sleep apnea and lung disease
  • Age
  • Obesity
  • Alcohol, especially binge drinking
  • Stress and poor sleep
  • Family history

Causes of Atrial Fibrillation

The sinus node acts as the heart's rhythm keeper, sending a signal through the two upper chambers and two lower chambers to keep the heartbeat on track. When this signal becomes chaotic, as occurs with A-fib, the chambers struggle to work together and result in a fast, irregular heart rhythm.

Typically, some sort of structural issue within the heart causes A-fib. Potential causes of atrial fibrillation include:

  • Heart disease
  • Heart defect
  • Heart attack
  • High blood pressure
  • Heart valve conditions
  • Lung disease
  • Viral infections
  • A condition of the sinus node
  • Thyroid disease
  • Stress due to illness
  • Use of stimulants

Symptoms of Atrial Fibrillation

Common A-fib symptoms include:

  • Palpitations (a fluttering, fast heartbeat)
  • Weakness or tiredness
  • Shortness of breath
  • Chest pain or tightness
  • Dizziness or lightheadedness
  • Fainting spells

Commonly, patients report an increase of A-fib symptoms at night. The symptoms of A-fib can serve as a warning sign for a patient to seek medical attention.

How to Diagnose Atrial Fibrillation

When diagnosing A-fib, a cardiologist will first conduct a medical history and physical examination. Listening to the heart with a stethoscope is often enough to detect an irregular heartbeat, but the cardiologist will likely order tests or procedures to rule out other possible conditions, such as:

Treatment Options for Atrial Fibrillation

The goal of treatment for A-fib is to reset or control the heart rhythm while preventing blood clots that can lead to stroke. The Brigham and Women’s Cardiac Arrhythmia Service offers state-of-the-art atrial fibrillation treatment and comprehensive cardiovascular care in a world-class medical facility. It is important to treat atrial fibrillation promptly because the condition can worsen over time as the heart muscles weaken, making it even more difficult for the atria to function properly.

Treatment may involve several options, including medication, ablation, therapy and surgery. Specialists from the Cardiac Arrhythmia Service develop individualized treatment plans for patients based on:

  • Age
  • Overall health
  • Medical history
  • Severity of the disease
  • Tolerance for specific medications or procedures
  • Expectations for course of the disease
  • Presence of other conditions

Atrial Fibrillation Treatment

Medication for Atrial Fibrillation
Surgery for Atrial Fibrillation

If you are having surgery or a procedure, you will likely be scheduled for a visit to the Watkins Clinic for pre-operative information and tests. The day of surgery, your care will be provided by surgeons, anesthesiologists and nurses who specialize in surgery for patients with atrial fibrillation. After surgery, you will go to the post-surgical care unit, where you will receive comprehensive care from an experienced surgical and nursing staff.

During your surgery, family and friends can wait in the Shapiro Family Center. Staff members will provide surgery updates, and caregivers who leave the hospital will be contacted by cell phone.

Atrial Fibrillation FAQs

Is Atrial Fibrillation Life Threatening?

While A-fib typically is not life-threatening, it can increase the risk of stroke if left untreated.

What Are the Potential Complications of Atrial Fibrillation?

An irregular heart rhythm brought on by A-fib can increase the risk of blood clots, which furthers the chance of stroke, heart failure or other heart conditions.

Is Atrial Fibrillation Considered Heart Disease?

A-fib is a heart condition, the most common form of heart arrhythmia. If left untreated, A-fib can lead to additional heart problems.

How Common is Atrial Fibrillation?

A-fib affects more than five million adults in the United States every year. A-fib is most common in older people, affecting one in 10 people over the age of 80.

What is a Normal Heart Rate for Someone with Atrial Fibrillation?

The normal heart rate for someone without A-fib typically runs from 60-100 beats per minute, while a patient with A-fib may see a heart rate jump to 100-200 beats per minute.

What Is the Difference Between Atrial Fibrillation and Heart Palpitations?

An irregular heart rhythm from A-fib is erratic, whereas heart palpitations increase the heart rate in a fixed rhythm that eventually returns to normal.

Our Expertise in Atrial Fibrillation

At Brigham and Women’s Hospital, our atrial fibrillation specialists provide expert evaluation and diagnosis with the aid of the latest in advanced imaging technologies. Treatment is provided by some of the world’s most experienced physicians in cardiac electrophysiology (the study of the heart’s electrical system). Together, they perform more than 3,000 procedures annually, utilizing the latest medications, devices and innovative care approaches. We offer patients personalized care and expertise that includes ongoing communication and education throughout treatment, outpatient care and follow-up.

Multidisciplinary Care

Patients receive care from cardiologists, interventional cardiologists, cardiac surgeons, cardiovascular imaging experts and radiologists, and anesthesiologists. They work alongside nurses, physician assistants, physical therapists, dietitians and social workers to achieve outstanding outcomes for our patients.

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