Atrial Fibrillation (AF) is a type of irregular heartbeat, often caused when the two upper chambers of the heart beat unpredictably and sometimes rapidly. These irregular heartbeats can cause blood to collect in the heart and potentially form a clot, which can travel to a person’s brain and cause a stroke. It is the leading risk factor for stroke.
If a clot leaves the heart and travels to the brain, it can cause a stroke by blocking the flow of blood through cerebral arteries. Some people with AF have no symptoms, but others may experience a fluttering feeling in the area of the chest above the heart, chest pain, lightheadness or fainting, shortness of breath, and fatigue. AF is diagnosed by an electrocardiogram (ECG), a device that records the heart’s electrical activity. Other tests are often performed to rule out contributing causes, such as high blood pressure, an overactive thyroid gland, heart failure, faulty heart valves, lung disease, and stimulant or alcohol abuse. Some people will have no identifiable cause for their AF.
Once in the brain, a larger clot can block larger vessels. The bigger the vessel that is blocked, the greater the amount of brain tissue that is likely to be affected. And so it follows that the greater the amount of brain that has its blood supply cut off, the greater the chance of a severe stroke, death and disability.
To prevent strokes related to AF, Neurologist often prescribe medications to prevent formation of clots in the heart, which can travel to the brain and cause stroke.