Atrial fibrillation is associated with an increased risk of embolic strokes and is present in about one-fourth of all patients undergoing cardiac surgery. Closure of the left atrial appendage (LAA) can effectively reduce the risk of neurological events and is now a class IB recommendation in the most recent ESC/EACTS AF guidelines. The working group "Heart Rhythm Disorders" of the German Society for Thoracic and Cardiovascular Surgery (DGTHG) evaluates the current state of clinical research and recommends concomitant LAA closure in patients with preoperative atrial fibrillation as a routine part of heart surgeries.