Atrial fibrillation (AF) is an abnormal heart rhythm. It occurs when the upper chambers of the heart do not beat normally, and this can lead to an irregular heart beat. Although some people can feel when their heart is irregular, many people are asymptomatic.
Atrial fibrillation can occur after heart or lung surgery, but it can also occur in people who are otherwise healthy. A short period of atrial fibrillation after surgery is very common, and is usually treated with medications to return your heart to a normal rhythm. Most people who have an irregular heart rhythm after surgery will recover in a short time.
People who have atrial fibrillation for longer periods are at risk for developing blood clots in the heart. These clots can sometime be dislodged from the heart and travel to other parts of the body, resulting in a stroke. Depending on your specific medical conditions, your doctor may want you to take blood thinners to reduce the risk of stroke if you have atrial fibrillation.