Atrial fibrillation is an abnormal heart rhythm that starts in the upper chambers of the heart.
What is going on in the body?
The top chambers of the heart are called the atria. They feed blood into the lower chambers, called ventricles. In some people, the atria begin to fibrillate, or twitch. This causes the normal, regular beating of the heart to change to a random, chaotic rhythm. This is called atrial fibrillation.
What are the causes and risks of the disease?
Atrial fibrillation is the most common heart rhythm disturbance for which people seek medical attention. It is most common in elderly individuals. It is more common in men than in women.
Risk factors for atrial fibrillation include the following:
congestive heart failure, in which the weakened heart fails to pump blood effectively throughout the body
coronary artery disease
heart valve disorders
herbal remedies, including ephedra and ginseng
high blood pressure
hyperthyroidism, or an overactive thyroid gland
open heart surgery
pulmonary embolism, which is a blockage in the blood supply to the lungs
too much alcohol intake