[Postoperative atrial fibrillation after open heart surgery]

New-onset postoperative atrial fibrillation (POAF) affects 30-50% of all patients after open heart surgery. This condition is associated with an increased risk of heart failure, future atrial fibrillation, and ischemic stroke, but no causal relationship has yet been established. Patients who develop POAF after cardiac surgery should therefore be closely monitored due to the increased risk of heart failure and recurrence of atrial fibrillation. At the same time, recent studies using implantable monitors show that patients with POAF after coronary artery bypass surgery have a very low atrial fibrillation burden after the first postoperative month. It is still unclear whether anticoagulant therapy reduces the risk of ischemic stroke in these patients. Any decision regarding anticoagulation treatment should therefore be based on an individual assessment of the patient's risk of both stroke and bleeding.