Atrial fibrillation, also known as abnormal heart rhythm or atrial flutter, is a heart rhythm disorder involving a rapid heart rate. In cases of atrial fibrillation, the two upper chambers of the heart, called atria, contract in a very disorganized and abnormal manner.

The heart has four chambers. Normally, they contract in a very specific, coordinated way, guided by electrical impulses that originate in the sinoatrial node - the heart's natural pacemaker. When a problem occurs along this electrical conduction system, various arrhythmias may occur, including atrial fibrillation.

Atrial fibrillation can affect both men and women. It becomes more common with increasing age.

Learn more about Atrial Fibrillation


Individuals may not be aware of an abnormal heartbeat, especially if it has been happening for some time. Symptoms include:

  • Pulse that feels rapid, racing, pounding, fluttering or too slow

  • Pulse that feels irregular

  • Palpitations, a sensation of feeling the heart beat in the chest

  • Shortness of breath while lying down

  • Confusion

  • Dizziness, light-headedness

  • Fainting

  • Fatigue

A health care provider should be consulted if symptoms of atrial fibrillation or flutter are present.

Atrial fibrillation can be caused by alcohol use, especially binge drinking. It can also be caused by congestive heart failure, coronary artery disease, heart surgery, high blood pressure (hypertension), hypertrophic cardiomyopathy, medications, an overactive thyroid gland (hyperthyroidism), pericarditis or valvular heart disease.

Atrial fibrillation can cause fainting, heart failure, stroke or even death.

At Texas Health, we have advanced diagnostics to help us understand individual conditions and plan a course of treatment.


In certain cases, atrial fibrillation may need emergency treatment to get the heart back into normal rhythm. This treatment may involve defibrillation or IV medication.

Long-term treatment varies depending on the cause of the atrial fibrillation or flutter. Medications to slow the heartbeat may include beta-blockers, calcium channel blockers, anti-arrhythmic medications and blood thinners.

Some patients with atrial fibrillation, rapid heart rates and intolerance to medication may need a catheterization procedure called radiofrequency ablation.

Texas Health is committed to providing quality care to heart and vascular patients throughout North Texas and beyond. While various technologies and services are discussed here, not all of our hospitals offer every treatment and diagnostic technology highlighted. Call 1-877-THR-WELL to learn more about heart and vascular services at a Texas Health hospital near you.

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