What is AFib?

Atrial fibrillation is an arrhythmia where the upper heart chambers contract rapidly due to irregular electrical signals, explains the National Heart, Lung, and Blood Institute. During atrial fibrillation, the electrical signals don't begin in the sinoatrial node, as they do during normal heart rhythms, but spread throughout the atria abnormally.

According to Mayo Clinic, untreated atrial fibrillation can lead to stroke or heart failure. Treatments for atrial fibrillation depend on what is causing the abnormal rhythm. If a patient has thyroid problems, treating the condition can improve symptoms of atrial fibrillation. Other treatments to reset the normal heart rate and rhythm include anti-arrhythmic drugs and electrocardioversion, where the heart is briefly shocked so that it beats at a normal rate and rhythm.