Why is a stroke a possible complication of atrial fibrillation?
The erratic heart rhythm of AF causes turbulent blood flow within the heart chambers. This sometimes leads to a small blood clot forming in a heart chamber. A clot can then travel in the blood vessels until it gets stuck in a smaller blood vessel in the brain (or sometimes in another part of the body). Part of the blood supply to the brain may then be cut off, which causes a stroke. Therefore, the main complication of AF is an increased risk of having a stroke. The risk of developing a blood clot and having a stroke varies, depending on various factors. The level of risk is divided into three categories: high, medium and low risk: • High risk means that, without treatment, you have about a 6-12 in 100 chance (sometimes higher) of having a stroke in the next year. People in the high risk group include those: • who have already had a stroke or known blood clot, or • are aged 75 years or older who also have one of the following risk factors: high blood pressure, diabetes or a cardiovascul
