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Atrial fibrillation (also known as atrial fib, A-fib or AF) is one of the most common types of arrhythmia or heart rhythm abnormalities. A-fib occurs when the normal electrical pathway in the heart is "overridden" by a clump of cells in the left side of the heart. This bunch of cells fires off electricity rapidly and causes the top chamber to “dance” or quiver. This, in turn, causes the bottom chambers of the heart to beat irregularly, and sometime, faster than normal. According to the CDC:

  • It is estimated that 12.1 million people in the United States will have A-fib in 2030.
  • More than 454,000 hospitalizations with A-fib as the primary diagnosis happen each year in the United States.
  • A-fib increases a person’s risk for stroke, accounting for about 1 in 7 strokes due to its tendency to cause blood clots

For this and many other reasons, effective treatment for AF is imperative.

Symptoms of Atrial Fibrillation

With atrial fibrillation, the electrical signals in the atria (the two small chambers of the heart) fire fast and chaotically, causing the atria to quiver instead of contract. As a result, electrical signals then arrive in the ventricles in an irregular fashion, causing a rapid and disorganized heartbeat. Additionally, when the atria do not contract effectively, blood may pool and/or clot, putting the patient at higher risk for stroke. Patients with AF feel:

  • Strange heartbeat sensations
  • Dizziness
  • Fainting
  • Fatigue
  • Shortness of breath and other symptoms 


A-Fib Risks

Atrial fibrillation is serious. It is the leading cause of stroke, as inefficient pumping causes blood to pool or become thicker in the heart chambers, increasing the chance of a clot forming, breaking loose and traveling to the brain. In some patients when the heart rate is fast, A-fib can promote heart failure as the pumps of the heart are not as efficient as they are in normal rhythm.

Although A-fib may cause chest pain in some patients, A-fib and heart attacks are two completely different issues. In the "house" known as the heart, A-fib in an electrical problem and heart attacks are plumbing problems.

Experts in Atrial Fibrillation Diagnosis and Treatment

Froedtert & MCW physician specialists offer a unique approach for patients with atrial fibrillation and atrial flutter (a quick heartbeat that can lead to atrial fibrillation), offering comprehensive diagnosis, treatment and follow-up care.

Hybrid, Team Approach to Patient Care

Physicians may recommend several different treatment approaches depending on what is right for the patient. And, because the team is part of an academic medical center, patients have access to the latest diagnostic and treatment procedures.

Exceptional Physician Specialists

Patients benefit from the combined expertise of the multidisciplinary team of arrhythmia physician specialists, including electrophysiologists (cardiologists trained in heart rhythm disorders), heart surgeons, cardiologists and other specialists assembled based on the patient’s condition. Learn more about our exceptional staff.


Because we are a leading academic medical center, research is central to our work. Medical College of Wisconsin physicians are continually participating in and conducting significant research studies to further understand the causes of atrial fibrillation and identify innovative treatments. Our patients can participate in local and national clinical trials, which can give them access to the latest treatment options for atrial fibrillation.

Comprehensive Diagnostics

We offer a full range of imaging techniques and diagnostic studies to diagnose atrial fibrillation. Tests are conducted by electrophysiologists and other physicians who specialize in heart rhythm conditions. Learn more about diagnostic procedures for arrhythmia.

Treating Atrial Fibrillation

For many patients, a wide variety of treatments are available for atrial fibrillation, including medications, cardioversion and other procedures. When more aggressive treatment is required physicians may recommend catheter ablation, cryoballoon ablation or CryoMaze or maze surgery to eliminate the source of the irregular heart rhythm.