Atrial fibrillation (A-fib) is an irregular and often very rapid heart rhythm (arrhythmia) that can lead to blood clots in the heart. A-fib increases the. Atrial fibrillation is a heart condition that causes an irregular and often abnormally fast heart rate. A normal heart rate should be regular and between Atrial fibrillation (AF) is a common abnormal heart rhythm or arrhythmia. It causes your heart to beat abnormally, which might feel like your heart is. Atrial fibrillation (also called AFib or AF) is a quivering or irregular heartbeat (arrhythmia) that can lead to blood clots, stroke. No information is available for this page. Atrial fibrillation (AF), also called Afib, is a condition which causes an irregular and often rapid heart rate, and can lead to stroke and heart failure. It is. ESC Clinical Practice Guidelines. Atrial fibrillation (AF) poses a significant burden to patients, physicians, and healthcare systems globally. Substantial. Atrial fibrillation (AF) is an arrhythmia. It results from irregular, disorganized electrical activity in the atria, leading to irregular ventricular. Atrial fibrillation is one of the most common types of arrhythmias, which are irregular heart rhythms. Atrial fibrillation causes your heart. Working to provide information, support and access to established, new or innovative treatments for Atrial Fibrillation (AF).