Atrial fibrillation - Complications of atrial fibrillation
NHS Choices Medical Reference
The main complication of atrial fibrillation is an increased risk of having a stroke. In extreme cases, it can lead to heart failure.
When the upper chambers of the heart, called the atria, do not pump efficiently, as in atrial fibrillation, there is a risk of blood clots forming.
These blood clots may move into the lower chambers of the heart, called the ventricles, and get pumped into the blood supply to the lungs or the general blood circulation.
Clots in the general circulation can block arteries in the brain, causing a stroke.
Atrial fibrillation increases the risk of a stroke by around four to five times. However, the risk depends on a number of factors, including age and whether you have high blood pressure, heart failure, diabetes and a previous history of blood clots.
If your atrial fibrillation is persistent, it may start to weaken your heart. In extreme cases, it can lead to heart failure, where your heart cannot pump blood around your body efficiently.