Atrial fibrillation (also known as AFib) is the most common type of abnormal heartbeat, or arrhythmia. AFib affects the upper chambers of the heart, which are called the atria. If these chambers beat irregularly instead of steadily, blood may not exit the heart as it should, which can cause blood clots to form. Those clots form the physical, dangerous link between AFib and stroke.

Blood clots are often responsible for ischemic stroke, which is the most common type of stroke. This occurs when a clot or a buildup of plaque occurs in an artery of the brain, which blocks blood flow and robs the brain of vital oxygen and nutrients. Less commonly, an artery in the brain can burst and leak blood into the organ, which is called a hemorrhagic stroke.

A variety of factors can increase your risk for stroke, including several cardiovascular conditions. At the top of the list is high blood pressure, but AFib is another common risk factor – and a potent one. If you have AFib, your risk of stroke is five times higher than someone without AFib.

AFib causes the atria to tremble instead of strongly and efficiently contracting. As a result, instead of leaving the heart and racing out to the rest of the body, some blood may pool in the muscle. That pooling can lead to clot formation, often in a small sac in the left atrium called the left atrial appendage.

Clots that form in the heart don’t always remain there. Some may leave the muscle and make their way through the network of arteries to a vessel in the brain. If a clot becomes lodged in a brain artery, an ischemic stroke may occur.

Symptoms don’t always occur with AFib, but it can cause your heart to flutter or beat rapidly. You may feel lightheaded or unusually tired or have trouble breathing. If you experience any of those symptoms, promptly see your primary care physician. He or she may refer you to a cardiovascular specialist.

It may not be possible to stop every stroke related to AFib, but you and your medical team can do a lot to manage your risk. That starts with quickly seeking medical attention for symptoms – the sooner you receive a diagnosis of AFib, the quicker treatment can begin. Treatment options range from medications to regulate heart rhythm and prevent blood clots to surgery and catheter-based procedures.

Your habits and everyday choices also play a major role in your risk of stroke due to AFib. In addition to managing AFib, you can stop smoking if you smoke, exercise regularly and eat a healthy diet – both will help you maintain a healthy weight, which can also reduce your stroke risk – and manage high blood pressure.

Learn how the Watchman Procedure at Washington Health System can help prevent stroke from AFib.