Atrial fibrillation (AFib) is an irregular, often rapid heart rhythm. If left untreated, AFib can cause blood clots in the heart, increasing the risk of stroke, heart failure, and other heart-related complications. 

AFib is often caused by changes in the heart’s tissue or in the electrical signaling that helps the heart beat. The electrical signals that make the heart pump start in an area of the upper right chamber of the heart called the sinoatrial node, which makes the right and left atria contract and pump blood to the lower heart chambers, or ventricles. When a person has AFib, abnormal electrical signals disrupt this process, causing the heart’s upper chambers to contract irregularly and compromising the ability of the upper and lower chambers to work together to pump blood effectively.  

Changes in the heart that can lead to AFib may include aging, heart disease, infection, or genetics. Additionally, tissue changes that affect the heart’s ability to contract rhythmically may include fibrosis, inflammation, thinning or thickening of the heart walls, reduced blood flow to the heart, or a buildup of proteins, cells, or minerals in heart tissue. 

Some people with AFib may not notice any symptoms at all, or may have symptoms that come and go. Symptoms may include a fast, fluttering, or pounding heartbeat; chest pain; dizziness and lightheadedness; fatigue and weakness; shortness of breath; and reduced ability to exercise. Lifestyle choices or experiences that can increase a person’s risk of AFib include heavy alcohol use; use of illegal drugs; participation in endurance sports or vigorous workouts; smoking; and stress. 

AFib needs to be diagnosed by a healthcare professional. Medications may be required to control the heart rate and prevent blood clots. 

Article Source: Mayo Clinic, The National Heart, Lung, and Blood Institute