Atrial fibrillation is a rhythm disorder (arrhythmia) in which the right and left atrium (filling chambers of the heart) contract in an irregular manner. The atria do not contract at the same time as the ventricles (pumping chambers).
Atrial fibrillation affects 1-2% of the population, and the incidence increases with age. Commonly associated conditions include:
If untreated, the irregular rhythm can result in formation of thrombus (clot) in the atria. These clots may become dislodged and travel in the bloodstream to other areas of the body, resulting in blockages of major arteries.
Complications of atrial fibrillation include:
Medical treatment of atrial fibrillation involves anticoagulation and various strategies to convert the heart back into a regular rhythm. Anticoagulation and antiarrhythmic medications must be carefully monitored to avoid side effects such as bleeding or other arrhythmias.
Surgical treatment of atrial fibrillation is highly effective and depends on the length and persistence of the fibrillation. Patients with intermittent, short-term atrial fibrillation have the highest rates of cure. Typical operations include pulmonary vein isolation or the modified Maze III operations using radiofrequency energy to ablate (eliminate) the irregular rhythm. Surgery is indicated for both isolated atrial fibrillation and for patients requiring simultaneous open-heart operations for other conditions, such as valvular or coronary artery disease.