Atrial fibrillation

Atrial fibrillation (AF) is a cardiac arrhythmia characterized by rapid, disorganized electrical activity in the atria, producing an irregular ventricular rhythm and ineffective atrial contraction. Reduced atrial mechanical function can promote blood stasis, particularly in the left atrial appendage, increasing the risk of thromboembolism, including ischemic stroke and systemic embolism. AF commonly occurs in the setting of age, hypertension, diabetes, obesity, coronary artery disease, myocardial infarction, or heart failure, although it may also arise in association with genetic susceptibility, structural remodeling, epicardial adipose tissue, or treatment-related cardiac injury.

Clinical management focuses on rhythm or rate control, assessment of thromboembolic risk, and prevention of ischemic stroke. Oral anticoagulants, including direct oral anticoagulants, may reduce thromboembolic risk but require consideration of major bleeding and other bleeding risks. Electrocardiography remains central to diagnosis, while handheld mobile ECG devices and artificial intelligence methods are being evaluated for detection and prediction of AF. Before cardioversion, assessment of the left atrial appendage by cardiac CT may help evaluate thrombus risk. Current research also examines polygenic risk scores, symmetric dimethylarginine, cardiometabolic therapies such as glucagon-like peptide-1 receptor agonists, and cardiac radiation exposure as potential contributors to AF risk or its clinical stratification.